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Question 4501Question

Three different wooden boards have lengths of 34\frac{3}{4} meters, 910\frac{9}{10} meters, and 158\frac{15}{8} meters, respectively. A carpenter wants to cut them into smaller pieces of equal length such that no material is wasted. What is the maximum possible length of each smaller piece?

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Answer: 340\frac{3}{40} meters

Answer

The correct answer is 340\frac{3}{40} meters.
To find the maximum equal length that can be cut from all three boards, we must find the Highest Common Factor (HCF) of their lengths. The formula for the HCF of fractions is the HCF of the numerators divided by the LCM of the denominators. The numerators are 3,9,3, 9, and 1515, yielding an HCF of 33. The denominators are 4,10,4, 10, and 88, yielding an LCM of 4040. Thus, the maximum length is 340\frac{3}{40} meters.

Step-by-Step Solution

1
Identify the mathematical operation required.
The problem asks for the 'maximum possible length' that can evenly divide all three board lengths without remainders. This requires finding the Highest Common Factor (HCF) of the three fractions.
Cutting multiple items into the largest possible equal smaller pieces is a classic application of HCF.
2
Recall the formula for finding the HCF of fractions.
HCF of fractions=HCF of NumeratorsLCM of Denominators\text{HCF of fractions} = \frac{\text{HCF of Numerators}}{\text{LCM of Denominators}}
This is the standard rule for finding the greatest common divisor of a set of rational numbers.
3
Calculate the HCF of the numerators (3,9,153, 9, 15).
The factors of 33 are 1,31, 3. The factors of 99 are 1,3,91, 3, 9. The factors of 1515 are 1,3,5,151, 3, 5, 15. The highest common factor is 33.
The numerator of our final fraction must be the HCF of the given numerators.
4
Calculate the LCM of the denominators (4,10,84, 10, 8).
The prime factorization of 44 is 222^2. For 88, it is 232^3. For 1010, it is 2×52 \times 5. The LCM takes the highest power of each prime present: 23×5=8×5=402^3 \times 5 = 8 \times 5 = 40.
The denominator of our final fraction must be the LCM of the given denominators.
5
Combine the results to find the final HCF.
340\frac{3}{40} meters.
Applying the formula from Step 2 with the values found in Step 3 and Step 4.

Key Concept

HCF and LCM of Fractions
Question 4502Question

Arrange the following words in a logical sequence as they would appear in an English dictionary:

Drag items to arrange them in the correct order

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Answer

The correct dictionary order is: Objection, Objective, Obligation, Oblivion, Obscure.
By strictly applying alphabetical ordering rules, we group the words by their initial letters and then differentiate within groups. 'Objection' precedes 'Objective' because 'o' comes before 'v'. 'Obligation' precedes 'Oblivion' because 'g' comes before 'v'. 'Obscure' is last because 's' comes after 'j' and 'l'.

Step-by-Step Solution

1
Compare the first three letters of all words.
All words start with 'Ob'. The third letters are 'j' (Objection, Objective), 'l' (Obligation, Oblivion), and 's' (Obscure).
Dictionary order strictly follows alphabetical order from left to right.
2
Sort the groups based on the third letter.
The 'j' group comes first, followed by the 'l' group, and finally the 's' group (Obscure).
In the alphabet, 'j' precedes 'l', which precedes 's'.
3
Order the words within the 'j' group (Objection, Objective).
'Objection' comes before 'Objective'.
The first seven letters (O-b-j-e-c-t-i) are identical. The eighth letter 'o' in Objection comes before the 'v' in Objective.
4
Order the words within the 'l' group (Obligation, Oblivion).
'Obligation' comes before 'Oblivion'.
The first three letters (O-b-l) are identical, and the fourth letter is 'i' for both. The fifth letter 'g' in Obligation comes before the 'v' in Oblivion.
5
Combine the sorted groups into the final sequence.
Objection, Objective, Obligation, Oblivion, Obscure.
This maintains the strict alphabetical sorting established in the previous steps.

Key Concept

Dictionary Arrangement and Alphabetical Order
Question 4503Question

Consider the following 88 mathematical expressions:

I. π227\pi - \frac{22}{7}
II. 273\frac{\sqrt{27}}{\sqrt{3}}
III. (32)2(\sqrt{3} - \sqrt{2})^2
IV. The infinite decimal 0.1011011100.101101110\dots (where the number of consecutive 11 s increases by one each time)
V. 1.4141.414
VI. 10×2.5\sqrt{10} \times \sqrt{2.5}
VII. e0e^0
VIII. 2+8\sqrt{2} + \sqrt{8}

How many of the above expressions evaluate to a rational number?

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Answer: 4

Answer

Exactly 4 of the expressions evaluate to a rational number.
Out of the 8 expressions provided, exactly 4 result in rational numbers: Expression II (simplifies to 3), Expression V (terminating decimal 1414/1000), Expression VI (simplifies to sqrt(25) = 5), and Expression VII (simplifies to 1). The remaining 4 expressions yield irrational results.

Step-by-Step Solution

1
Evaluate expression I (pi minus 22/7)
The expression evaluates to an irrational number.
The number pi is irrational, while 22/7 is a rational approximation. The difference between an irrational number and a rational number is always irrational.
2
Evaluate expression II (sqrt(27) / sqrt(3))
The expression simplifies to 3, which is a rational number.
Using the properties of radicals, sqrt(27) / sqrt(3) = sqrt(27/3) = sqrt(9) = 3.
3
Evaluate expression III (square of (sqrt(3) - sqrt(2)))
The expression expands to 5 - 2*sqrt(6), which is an irrational number.
Applying the binomial square formula (a-b)^2 = a^2 - 2ab + b^2 yields 3 - 2*sqrt(6) + 2. Since sqrt(6) is irrational, the entire expression is irrational.
4
Evaluate expression IV (the pattern decimal 0.101101110...)
The expression is an irrational number.
The decimal is non-terminating and non-periodic (the pattern changes constantly by adding an extra 1), which is the definition of an irrational decimal.
5
Evaluate expression V (1.414)
The expression is a rational number.
1.414 is a terminating decimal. Any terminating decimal can be written as a fraction of integers (1414/1000), making it rational.
6
Evaluate expression VI (sqrt(10) * sqrt(2.5))
The expression simplifies to 5, which is a rational number.
Multiplying the terms inside the radicals gives sqrt(10 * 2.5) = sqrt(25) = 5.
7
Evaluate expression VII (e^0)
The expression simplifies to 1, which is a rational number.
Any non-zero real number raised to the power of 0 equals 1.
8
Evaluate expression VIII (sqrt(2) + sqrt(8))
The expression simplifies to 3*sqrt(2), which is an irrational number.
sqrt(8) can be simplified to 2*sqrt(2). Adding sqrt(2) gives 3*sqrt(2), which remains an irrational product.
9
Count the total number of rational expressions
Expressions II, V, VI, and VII are rational. Total count is 4.
Identifying the rational outcomes from the previous steps.

Key Concept

Properties and Definitions of Rational and Irrational Numbers
Estimated Time:2m 30s
Question 4504Question

Six friends—J, K, L, M, N, and O—are seated around a circular table facing the center. Each has a different profession: Chef, Doctor, Engineer, Lawyer, Pilot, and Teacher. The seating arrangement follows these conditions:

- The Doctor sits second to the left of M.
- K is an Engineer and sits immediately to the right of M.
- The Pilot sits exactly between J and the Lawyer.
- N sits exactly opposite the Teacher.
- O sits adjacent to the Doctor.
- The Chef sits immediately to the left of the Teacher.

Based on the given information, which of the following statements is true?

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Answer: L is the Lawyer and sits exactly opposite O.

Answer

The statement declaring that L is the Lawyer and sits exactly opposite O is true.
After deducing the full arrangement, O is identified as the Chef sitting at Seat 2, and L is identified as the Lawyer sitting at Seat 5. In an evenly spaced 6-seat circular arrangement, Seat 2 and Seat 5 are exactly opposite each other.

Step-by-Step Solution

1
Establish a reference point by placing M at the top (Seat 1).
M is at Seat 1. Facing the center means left is clockwise and right is counter-clockwise.
Setting a fixed starting point makes relative positioning easier in circular arrangements.
2
Apply the relative positioning clues for M.
The Doctor is second to the left (clockwise), so Seat 3 is the Doctor. K is the Engineer and is immediately to the right (counter-clockwise), so Seat 6 is K (Engineer).
These are direct spatial deductions based on M's position.
3
Determine the Teacher's position using the remaining clues.
The Chef is immediately to the left of the Teacher. If the Teacher were anywhere other than Seat 1, it would conflict with already placed people or leave no valid opposite seat for N. Thus, M is the Teacher (Seat 1), and the Chef is at Seat 2.
Testing all alternative positions for the Teacher systematically eliminates them.
4
Place N and O based on their specific constraints.
N is opposite the Teacher (Seat 1), placing N at Seat 4. O is adjacent to the Doctor (Seat 3). With Seat 4 occupied by N, O must be at Seat 2. Therefore, O is the Chef.
Direct placement logic based on open seats.
5
Place the Pilot, Lawyer, and J using the sequence constraint.
The Pilot sits exactly between J and the Lawyer. The only three available consecutive seats are 3, 4, and 5. Since Seat 3 is the Doctor (J), Seat 4 must be the Pilot (N), and Seat 5 must be the Lawyer.
Consecutive seating constraints can only fit into uninterrupted blocks of available seats.
6
Identify the final person and verify the options.
L is the only remaining person, so L sits at Seat 5 and is the Lawyer. The arrangement is: 1:M(Teacher), 2:O(Chef), 3:J(Doctor), 4:N(Pilot), 5:L(Lawyer), 6:K(Engineer).
Completing the puzzle allows for the evaluation of all statements.

Key Concept

Logical deductions based on left/right orientation in circular seating arrangements.
Question 4505Question

Four marine exploration vessels (Alpha, Beta, Gamma, and Delta) are deployed for oceanographic surveying. Each vessel begins facing a specific cardinal direction and executes a sequence of angular maneuvers as described below:

- Vessel Alpha: Starts facing North, rotates 135135^{\circ} clockwise, moves forward, and then rotates 4545^{\circ} anti-clockwise.
- Vessel Beta: Starts facing East, rotates 9090^{\circ} clockwise, moves forward, and then rotates 135135^{\circ} clockwise.
- Vessel Gamma: Starts facing South, rotates 4545^{\circ} anti-clockwise, moves forward, rotates 180180^{\circ} clockwise, and finally rotates 9090^{\circ} anti-clockwise.
- Vessel Delta: Starts facing West, rotates 135135^{\circ} anti-clockwise, moves forward, rotates 9090^{\circ} clockwise, and finally rotates 4545^{\circ} anti-clockwise.

Match each vessel with its final facing direction.

Click a left item, then click its matching right item

Items

Vessel Alpha
Vessel Beta
Vessel Gamma
Vessel Delta

Matches

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Answer

Vessel Alpha matches with East; Vessel Beta matches with North-West; Vessel Gamma matches with South-West; Vessel Delta matches with South.
Each vessel's final direction is calculated by applying its sequence of clockwise and anti-clockwise rotations mathematically or visually, starting from its initial cardinal direction.

Step-by-Step Solution

1
Calculate the final direction for Vessel Alpha by summing its angular turns from North.
North (0°) + 135° CW - 45° ACW = 90° (East).
Clockwise (CW) turns add to the angle and anti-clockwise (ACW) turns subtract, assuming North is 0° and measuring clockwise.
2
Calculate the final direction for Vessel Beta by summing its angular turns from East.
East (90°) + 90° CW + 135° CW = 315° (North-West).
Tracking successive CW rotations from 90° gives the final orientation on the 360° compass.
3
Calculate the final direction for Vessel Gamma by summing its angular turns from South.
South (180°) - 45° ACW + 180° CW - 90° ACW = 225° (South-West).
Alternating CW and ACW turns are added and subtracted respectively.
4
Calculate the final direction for Vessel Delta by summing its angular turns from West.
West (270°) - 135° ACW + 90° CW - 45° ACW = 180° (South).
Tracking all ACW and CW maneuvers determines the exact final coordinate.

Key Concept

Direction and Distance Test
Question 4506Question

As the District Magistrate overseeing land acquisition for a new National Highway bypass, you are confronted with a multifaceted conflict halting the project. Different stakeholder groups have raised distinct objections and demands. Match the following stakeholder positions with the most constitutionally aligned and proportionate administrative intervention you should initiate to de-escalate and resolve the conflict.

Click a left item, then click its matching right item

Items

Indigenous tribal community leaders demanding the preservation of sacred groves falling on the proposed alignment.
The National Highway Authority (NHA) project director insisting on immediate clearance, citing daily financial losses and rigid project deadlines.
Local commercial farmers supporting the highway but demanding compensation rates well above the statutory circle rate.
Environmental NGOs threatening a mass protest over the lack of a comprehensive regional flora impact assessment.

Matches

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Answer

Tribal leaders matched with micro-alignment review; NHA director matched with upholding statutory procedure; Farmers matched with evidence-based valuation; NGOs matched with independent ecological appraisal.
The correct pairings apply the core principles of public administration: upholding constitutional rights through participatory compromise with vulnerable communities, maintaining procedural integrity against executive pressure, ensuring objective fairness in financial disputes, and rectifying legal compliance gaps to address legitimate civil society grievances.

Step-by-Step Solution

1
Analyze the indigenous community's demand.
Identify that constitutional protections for tribal culture require a balanced compromise.
Total displacement would violate constitutional rights, while halting the project harms public interest, making micro-alignment the optimal solution.
2
Evaluate the NHA director's pressure tactics.
Determine that financial urgency does not justify bypassing law.
Administrative ethics dictate that statutory due process cannot be compromised for executive speed.
3
Address the commercial farmers' financial demands.
Apply the principle of legal objectivity to financial disputes.
Yielding to arbitrary demands sets a bad precedent; relying on transparent, market-based mechanisms within the law resolves disputes fairly.
4
Assess the NGOs' environmental concerns.
Recognize the procedural gap in environmental clearance.
Protests based on legitimate procedural lapses are best resolved by fulfilling the mandatory compliance requirements.

Key Concept

Proportionality and rule of law in multi-stakeholder conflict resolution
Question 4507Question

Consider the following statement and the two assumptions that follow it.

Statement:
"The National Meteorological Authority has issued an official advisory urging coastal farmers to delay the sowing of their Kharif crops by two weeks due to a predicted delay in the arrival of the southwest monsoon."

Assumptions:
I. Coastal farmers generally rely on the rainfall from the southwest monsoon for the successful cultivation of their Kharif crops.
II. Delaying the sowing of crops by two weeks will inevitably result in a lower agricultural yield for the upcoming harvest season.

Based on the statement provided, which of the following is correct?

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Answer: Only assumption I is implicit

Answer

The correct answer is that only the first assumption is implicit.
The first assumption provides the necessary logical link between the monsoon's delay and the need to delay crop sowing. Without this unstated dependence, the meteorological advisory has no logical basis. The second assumption is a speculation about future outcomes (an inference), not an underlying premise.

Step-by-Step Solution

1
Analyze the main statement to understand the author's primary directive and motivation.
The authority is advising farmers to delay planting specifically because the monsoon is delayed.
Identifying the cause-and-effect relationship in the statement is necessary to find what is taken for granted.
2
Evaluate the first candidate assumption against the statement.
Assumption I is implicit. If farmers did not rely on the monsoon, a delay in its arrival would not necessitate a delay in sowing.
An assumption is a premise that must be true for the argument or directive to logically stand.
3
Evaluate the second candidate assumption against the statement.
Assumption II is not implicit. A potential drop in yield is a speculated future consequence (an inference), not an assumption that prompted the advisory. In fact, the advisory is likely designed to protect the yield.
Assumptions must be distinguished from inferences; an assumption is an unstated foundation, while an inference is a conclusion drawn from the action.

Key Concept

Distinguishing between implicit premises (assumptions) and direct logical consequences (inferences) in administrative directives.
Question 4508Question

Six colleagues—Farah, Gauri, Hasan, Imran, Jamal, and Kiran—are seated in a single straight row facing North for a team meeting.

Read the following information to determine their exact seating positions:
1. Jamal sits third to the right of Farah.
2. Neither Jamal nor Farah sits at the extreme ends of the row.
3. Hasan sits to the immediate left of Gauri.
4. Kiran does not sit at the extreme right end of the row.

Arrange the colleagues in their correct seating order from left (Position 1) to right (Position 6).

Drag items to arrange them in the correct order

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Answer

The correct seating order from left to right is: Kiran, Farah, Hasan, Gauri, Jamal, and Imran.
The correct sequence from left to right is Kiran, Farah, Hasan, Gauri, Jamal, and Imran. By deducing the fixed spacing between Farah and Jamal (who must occupy positions 2 and 5 to avoid the ends), the remaining adjacent seats (3 and 4) are strictly restricted to Hasan and Gauri. Kiran is assigned to the left end (Position 1) because the right end is forbidden for her by the constraints, leaving Imran to take the final open seat at the right end (Position 6).

Step-by-Step Solution

1
Determine the seating positions of Farah and Jamal.
Farah sits at Position 2 and Jamal sits at Position 5.
Jamal is third to the right of Farah. Since neither can sit at the extreme ends (Positions 1 and 6), Farah must be at Position 2, which places Jamal at Position 5 (2 + 3 = 5).
2
Determine the seating positions of Hasan and Gauri.
Hasan sits at Position 3 and Gauri sits at Position 4.
Hasan is immediately to the left of Gauri. The only two adjacent empty seats in the row (which currently has Positions 1, 3, 4, and 6 empty) are Positions 3 and 4.
3
Determine the seating positions of Kiran and Imran.
Kiran sits at Position 1 and Imran sits at Position 6.
The remaining empty seats are Positions 1 and 6. Since Kiran cannot sit at the extreme right end (Position 6), Kiran must sit at Position 1. Consequently, Imran takes the last remaining seat at Position 6.

Key Concept

Linear Seating Arrangement with Negative Constraints
Question 4509Question

You are the Municipal Commissioner of a rapidly expanding city. A severe outbreak of a vector-borne disease has occurred in a densely populated, unauthorized slum settlement. The slum is situated on prime municipal land previously earmarked for a commercial complex. While local health workers request the immediate deployment of emergency medical camps, some municipal officials advise you to use this health crisis as an opportunity to evict the squatters, arguing that the area is inherently unhygienic and illegal.

Arrange the following courses of administrative action from the most ethically sound to the least ethically sound.

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Answer

The most ethical approach prioritizes immediate humanitarian relief and public health containment inside the settlement. This is followed by offering external medical access (which is bureaucratically safe but lacks compassion), then withholding aid to leverage eviction, and finally, the most unethical action: exploiting the crisis to forcibly demolish the settlement under the guise of health measures.
The correct sequence prioritizes the fundamental right to life and immediate disaster containment over bureaucratic enforcement. An ethical administrator must first mitigate the immediate threat to human life before addressing the long-term legal status of the land. The sequence moves progressively from proactive humanitarian aid, to passive bureaucratic aid, to unethical coercion, and finally to outright abuse of power.

Step-by-Step Solution

1
Analyze the core ethical tension in the scenario.
The conflict is between the immediate humanitarian need to save lives during a health crisis and the administrative desire to clear illegal land encroachment.
Identifying the competing values at stake is necessary to evaluate administrative priorities.
2
Identify the most ethically sound action.
Deploying medical camps inside the settlement is ranked first.
The constitutional Right to Life and public health safety absolutely supersede property disputes or zoning laws.
3
Evaluate the intermediate actions.
Directing residents to outside hospitals is ranked second, while withholding aid to issue eviction notices is ranked third.
The former offers some medical help despite bureaucratic rigidity, whereas the latter weaponizes the crisis to force evictions, which is coercive and unethical.
4
Identify the least ethically sound action.
Using police force to demolish the settlement under the guise of sanitization is ranked last.
Deceiving the public and using a health disaster as a cover for violent displacement is a severe abuse of power and violates basic human dignity.

Key Concept

Administrative compassion, proportionality, and prioritization of the Right to Life over procedural enforcement during crises.
Question 4510Question

At exactly 10:10 AM, the hour hand of a standard analog clock is mechanically locked in its precise current position. The minute hand is then manually rotated forward (clockwise) by exactly 210210^{\circ}. Calculate the new angle (in degrees) formed between the hour and minute hands after this adjustment. Provide the smaller of the two possible angles.

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Answer: 35

Answer

The smaller angle between the hands after the adjustment is 35 degrees.
The correct calculation properly tracks the absolute angular positions from the 12 o'clock reference, correctly adding the 55^{\circ} proportional movement of the hour hand before finding the difference against the shifted minute hand.

Step-by-Step Solution

1
Find the initial position of the minute hand at 10:10 AM relative to the 12 o'clock mark.
The minute hand is at the 10-minute mark. Since each minute is 66^{\circ}, its position is 10×6=6010 \times 6^{\circ} = 60^{\circ}.
Establishing the starting angle of the minute hand is required before applying the rotation.
2
Find the exact initial position of the hour hand at 10:10 AM.
The 10 o'clock mark is at 10×30=30010 \times 30^{\circ} = 300^{\circ}. In 10 minutes, the hour hand drifts 10×0.5=510 \times 0.5^{\circ} = 5^{\circ}. The exact position is 300+5=305300^{\circ} + 5^{\circ} = 305^{\circ}.
The hour hand continuously moves. It does not stay exactly on the 10 while the minute hand moves.
3
Calculate the new position of the minute hand after the manual rotation.
The new minute hand position is 60+210=27060^{\circ} + 210^{\circ} = 270^{\circ}.
The problem states the minute hand is pushed forward by exactly 210210^{\circ}.
4
Calculate the angle between the locked hour hand and the new minute hand position.
The difference is 305270=35305^{\circ} - 270^{\circ} = 35^{\circ}.
Subtracting the smaller angular position from the larger one gives the acute interior angle between the hands.

Key Concept

Clock hand angular positioning, rotational displacement, and proportional hour-hand drift.
Question 4511Question

Trees are planted in a single straight line along a newly constructed highway. An Oak tree is the 42nd42^{\text{nd}} tree from the northern end of the line, and a Maple tree is the 58th58^{\text{th}} tree from the southern end. If there are exactly 1818 trees planted between the Oak tree and the Maple tree, what is the minimum possible total number of trees in this line?

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Answer: 80

Answer

80
To find the minimum possible number of trees, we must assume an overlapping scenario where the Maple tree is situated north of the Oak tree. In this arrangement, adding their positions from opposite ends (42+5842 + 58) double-counts the 1818 trees between them, as well as the Oak and Maple trees themselves. Therefore, the minimum total is 42+58(18+2)=8042 + 58 - (18 + 2) = 80.

Step-by-Step Solution

1
Identify the given positional values and the condition.
Oak tree = 42nd from North, Maple tree = 58th from South, trees between = 18.
These are the core variables needed to determine the total number of items in the line.
2
Determine the spatial arrangement required for a 'minimum' total.
The two trees must overlap. The Maple tree (counted from the South) must be located further North than the Oak tree (counted from the North).
If the positions do not overlap, we get the maximum possible number of trees. Overlapping them minimizes the total line length.
3
Apply the overlapping rank formula.
Total = (Position from one end) + (Position from other end) - (Number in between) - 2.
Adding the two ranks double-counts the items between them AND double-counts the two specific boundary items (the Oak and Maple trees) themselves.
4
Substitute the values and calculate the result.
Total = 42 + 58 - 18 - 2 = 100 - 20 = 80.
Computing the arithmetic expression gives the minimum number of trees.

Key Concept

Calculating minimum capacity in overlapping queues
Question 4512Question

Evaluate the mathematical logic governing the number pairs in Group X. Match each pair with its analog in Group Y that follows the exact same logical transformation.

Click a left item, then click its matching right item

Items

5:1245 : 124
9:909 : 90
27:8127 : 81
14:4314 : 43

Matches

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Answer

The correct pairings align identical underlying mathematical transformations: 5:1245:124 matches 7:3427:342 (cubes minus one), 9:909:90 matches 11:13211:132 (squares plus the number), 27:8127:81 matches 34:4934:49 (square of digit sum), and 14:4314:43 matches 19:5819:58 (multiplied by three plus one).
Each pair from Group X must be matched with a pair from Group Y that demonstrates the identical algebraic or numeric transformation rule. Solving these requires looking past simple differences and testing for squares, cubes, consecutive products, and digit manipulations.

Step-by-Step Solution

1
Analyze the first pair in Group X (5:1245 : 124) to determine its underlying logic.
The number 124124 is exactly 11 less than 125125 (535^3), revealing the rule n:n31n : n^3 - 1. Locating the same rule in Group Y yields 7:3427 : 342 since 731=3427^3 - 1 = 342.
Identifying the structural pattern involving powers allows for accurate cross-referencing with the target group.
2
Examine the second pair (9:909 : 90).
The number 9090 is the product of 99 and 1010, indicating the rule n:n(n+1)n : n(n+1). In Group Y, 11:13211 : 132 perfectly matches this logic because 11×12=13211 \times 12 = 132.
Testing consecutive multipliers is a standard method for identifying patterns in numeric classification.
3
Evaluate the third pair (27:8127 : 81).
While 8181 is a direct multiple (27×327 \times 3), no pair in Group Y shares this specific multiplier. Alternatively, summing the digits of 2727 gives 2+7=92+7=9, and 92=819^2=81. Applying this rule to Group Y isolates 34:4934 : 49, since (3+4)2=72=49(3+4)^2 = 7^2 = 49.
When standard arithmetic operations fail to yield a matching pair, analyzing digit-level operations is required.
4
Determine the rule for the final pair (14:4314 : 43).
The number 4343 is obtained via the operation 14×3+114 \times 3 + 1. The corresponding pair in Group Y is 19:5819 : 58, since 19×3+1=57+1=5819 \times 3 + 1 = 57 + 1 = 58.
Establishing a standard linear transformation finalizes the correct matching process.

Key Concept

Identifying multi-step mathematical operations, power series, and digit-based transformations to classify and match logical sequences.
Question 4513Question

Analyze the following three mathematical assertions concerning the classification and properties of numbers:

Assertion I: The expression 3216÷4×2\sqrt{32} - 16 \div 4 \times \sqrt{2} evaluates to an irrational number.
Assertion II: For any prime number pp that is strictly greater than 22, the value of p21p^2 - 1 is always a multiple of 88.
Assertion III: The number 00 is classified as a rational number and an even integer, but it is neither a prime nor a composite number.

Which of the assertions provided above are logically correct?

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Answer: Assertions II and III are the only correct statements.

Answer

Assertions II and III are the only correct statements.
Assertion II is mathematically accurate because the square of any odd prime minus one always factors into 4k(k+1)4k(k+1), which is a multiple of 88. Assertion III is also accurate as zero strictly fits the definitions of a rational number (0/10/1) and an even integer (0=2×00 = 2 \times 0), while being neither prime nor composite. Assertion I is false because correctly evaluating the expression from left-to-right yields 00, which is a rational number.

Step-by-Step Solution

1
Evaluate Assertion I using the correct order of operations (BODMAS/PEMDAS).
3216÷4×2=424×2=4242=0\sqrt{32} - 16 \div 4 \times \sqrt{2} = 4\sqrt{2} - 4 \times \sqrt{2} = 4\sqrt{2} - 4\sqrt{2} = 0.
Division and multiplication have equal precedence and are evaluated from left to right. The result, 00, is a rational number, making Assertion I false.
2
Analyze Assertion II for primes p>2p > 2.
All primes p>2p > 2 are odd, so p=2k+1p = 2k + 1 for some integer kk. Then p21=(2k+1)21=4k2+4k=4k(k+1)p^2 - 1 = (2k+1)^2 - 1 = 4k^2 + 4k = 4k(k+1).
Since kk and k+1k+1 are consecutive integers, one must be even. Thus, k(k+1)k(k+1) is an even integer, making 4k(k+1)4k(k+1) a multiple of 88. Assertion II is strictly true.
3
Verify the classifications of the number 00 in Assertion III.
00 can be written as 0/10/1 (rational), is divisible by 22 without remainder (even), and has no strictly positive divisors that satisfy the definition of primes or composites.
By standard mathematical definitions, 00 is rational, even, and neither prime nor composite. Assertion III is true.

Key Concept

Classification of numbers involving rational/irrational properties, algebraic properties of prime numbers, and the precise classification of zero.

Alternative Method

For Assertion II, students under time pressure can test the first few qualifying prime numbers (e.g., p=3321=8p=3 \Rightarrow 3^2-1=8; p=5521=24p=5 \Rightarrow 5^2-1=24) to quickly establish confidence in the truth of the statement without a formal algebraic proof.
Estimated Time:2m 0s
Question 4514Question

A genetic researcher is analyzing a three-generation pedigree chart containing six individuals: K, V, W, X, Y, and Z. The clinical notes reveal the following structure:

- Z is the paternal grandfather of Y.
- X is the only son of Z.
- W is the sister of X.
- V is the daughter-in-law of Z.
- K is the son of W.
- Y is the daughter of V.

Match the individuals on the left with their exact relationship to Y on the right.

Click a left item, then click its matching right item

Items

W
K
Z
V

Matches

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Answer

W matches with Paternal Aunt, K matches with First Cousin, Z matches with Paternal Grandfather, and V matches with Mother.
By systematically mapping the pedigree chart: Z is the grandfather, and his children are X (son) and W (daughter). X is married to V, and they have a daughter Y. W has a son K. Therefore, relative to Y, W is the paternal aunt, K is the first cousin, Z is the paternal grandfather, and V is the mother.

Step-by-Step Solution

1
Identify Y's father based on the grandfather relationship.
X is the father of Y.
Since Z is Y's paternal grandfather, Y's father must be a son of Z. The notes state that X is the only son of Z, so X must be the father.
2
Determine the relationship between V, X, and Y.
V is the mother of Y.
V is the daughter-in-law of Z, meaning she is married to Z's only son, X. Since Y is the daughter of V, and X is V's husband, V is Y's mother.
3
Determine the relationship of W to Y.
W is Y's paternal aunt.
W is the sister of X, who is Y's father. A father's sister is defined as a paternal aunt.
4
Determine the relationship of K to Y.
K is Y's first cousin.
K is the son of W. Since W is Y's aunt, her son K is Y's first cousin.

Key Concept

Multi-generational Family Tree Analysis
Question 4515Question
A satellite transmission system encodes data packets using a cyclic redundancy check (CRC). The checksum value is determined by finding the remainder when the expression T=7+12×53205T = 7 + 12 \times 53^{205} is divided by 2727. What is the correct checksum value?
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Answer: 22

Answer

The correct checksum value is 22.
The correct answer is 22. To find the remainder, we apply modular arithmetic to the base: since 27×2=5427 \times 2 = 54, we know 531(mod27)53 \equiv -1 \pmod{27}. Substituting this into the expression gives 7+12(1)2057 + 12(-1)^{205}. Because the exponent 205 is an odd number, (1)205=1(-1)^{205} = -1. Applying the order of operations, we multiply 12 by -1 to get -12, and then add 7, resulting in 5-5. Finally, to convert a negative remainder into a positive one, we add the divisor: 5+27=22-5 + 27 = 22.

Step-by-Step Solution

1
Identify the base and express it in modular arithmetic relative to the divisor 27.
531(mod27)53 \equiv -1 \pmod{27}
Simplifying the base to a small integer makes evaluating large exponents manageable. Since 5454 is a multiple of 2727, 5353 is exactly 11 less than a multiple.
2
Evaluate the exponentiated term using the simplified base.
53205(1)2051(mod27)53^{205} \equiv (-1)^{205} \equiv -1 \pmod{27}
Raising a negative one to an odd exponent results in negative one.
3
Substitute this result back into the expression and apply the proper order of operations (BODMAS).
7+12×(1)=712=5(mod27)7 + 12 \times (-1) = 7 - 12 = -5 \pmod{27}
According to mathematical rules, multiplication must be performed before addition.
4
Convert the negative remainder into a valid positive remainder.
5+27=22-5 + 27 = 22
A standard remainder must be a non-negative integer less than the divisor. We achieve this by adding the divisor to the negative result.

Key Concept

Modular Arithmetic and Fermat's/Euler's Remainder Concepts
Estimated Time:1m 15s
Question 4516Question

A positive integer XX is of the form X=2a×3bX = 2^a \times 3^b, where aa and bb are positive integers. It is known that XX has exactly 1515 positive factors. If XX is a multiple of 99 but is NOT a multiple of 2727, which of the following is the exact value of XX?

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Answer: 144

Answer

144
The correct value is determined by setting up the factor formula (a+1)(b+1) = 15. The only valid exponents that satisfy both the positive integer requirement and the divisibility constraints (b < 3 to avoid being a multiple of 27) are a=4 and b=2. Evaluating 2^4 \times 3^2 yields exactly 144.

Step-by-Step Solution

1
Identify the formula for the total number of positive factors.
For a prime factorization X=pa×qbX = p^a \times q^b, the number of positive factors is (a+1)(b+1)(a+1)(b+1).
This is a fundamental property of prime factorization.
2
Set up the equation based on the given number of factors.
(a+1)(b+1)=15(a+1)(b+1) = 15.
The problem explicitly states that XX has exactly 15 positive factors.
3
Determine the possible integer values for exponents aa and bb.
Since a1a \ge 1 and b1b \ge 1, we need factor pairs of 15 that are 2\ge 2. The only pair is 3×53 \times 5. This results in two possible cases: (a+1=5,b+1=3)(a+1=5, b+1=3) which gives a=4,b=2a=4, b=2; OR (a+1=3,b+1=5)(a+1=3, b+1=5) which gives a=2,b=4a=2, b=4.
Both aa and bb must be positive integers as defined in the question stem.
4
Apply the divisibility constraints to filter the two cases.
The condition 'NOT a multiple of 27' means 3b3^b cannot be divisible by 333^3, meaning bb must be strictly less than 33. Therefore, bb must be 22, which forces aa to be 44.
If b=4b=4 were chosen, XX would be a multiple of 8181, which is a multiple of 2727, violating the negative constraint.
5
Calculate the final value of XX.
X=24×32=16×9=144X = 2^4 \times 3^2 = 16 \times 9 = 144.
Substitute the verified exponents back into the original prime factorization.

Key Concept

Prime Factorization and Number of Factors
Estimated Time:1m 30s
Question 4517Question

Four identical delivery vans have different amounts of fuel remaining in their tanks. Arrange the vehicles based on their remaining fuel fraction from the least amount to the greatest amount.

Drag items to arrange them in the correct order

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Answer

The correct ascending sequence of fuel remaining is Van R, Van P, Van S, and Van Q.
By converting all given amounts into decimals (0.600.60, 0.750.75, 0.500.50, and 0.650.65), the values can be directly compared. 0.500.50 is the smallest and 0.750.75 is the largest, resulting in the correct ascending order of Van R, Van P, Van S, and Van Q.

Step-by-Step Solution

1
Convert all fractional fuel values into decimal form for straightforward comparison.
Van P (35\frac{3}{5}) becomes 0.60, and Van R (12\frac{1}{2}) becomes 0.50.
Converting all amounts to decimals provides a uniform format that is easier to logically order.
2
Order the decimal values from smallest to largest.
0.50<0.60<0.65<0.750.50 < 0.60 < 0.65 < 0.75.
The question specifically requires arranging the vehicles from the least amount of fuel to the greatest amount.

Key Concept

Converting basic fractions to decimals to compare and order numerical values.
Question 4518Question

A policy statement is given below, followed by two candidate assumptions. An assumption is something supposed or taken for granted. Identify which of the assumptions is/are implicit in the statement.

Statement:
"To alleviate the increasing load on the municipal electricity grid, the State Energy Commission has directed that all future commercial building projects must incorporate rooftop solar power systems."

Assumptions:
I. Rooftop solar systems can produce enough energy to significantly lower a commercial facility's dependence on the municipal grid.
II. The State Energy Commission plans to enforce similar solar power requirements for existing residential homes in the near future.

Which of the following is correct?

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Answer: Only assumption I is implicit

Answer

Only assumption I is implicit
The correct answer identifies that only the first assumption is implicit. For the State Energy Commission's directive to be logically sound and effective at alleviating the municipal grid load, the commission must inherently assume that commercial rooftop solar systems are capable of generating enough electricity to make a meaningful difference. If this were not assumed, the policy would lack a logical foundation. The second assumption involves a hypothetical future mandate for residential homes, which is a speculative prediction and completely unnecessary for the current commercial directive to be valid.

Step-by-Step Solution

1
Analyze the main statement to identify the intended goal and the prescribed action.
Action: Mandating solar systems for new commercial buildings. Goal: Alleviate the increasing load on the municipal grid.
Understanding the causal relationship between the policy action and its intended outcome is the first step in identifying unstated premises.
2
Evaluate Assumption I against the statement's logic.
Assumption I is implicit. It provides the logical bridge showing that the action (solar panels) will actually achieve the goal (reducing grid load).
For any administrative mandate to be rational, the policymaker must inherently assume that the mandated action will successfully contribute to the desired outcome.
3
Evaluate Assumption II against the statement's scope.
Assumption II is not implicit. It projects a separate, future policy expansion into the residential sector.
Assumptions must be foundational beliefs required for the current statement to make sense, not speculative inferences or predictions about future actions.

Key Concept

Statement and Assumptions: Distinguishing Implicit Premises from Future Inferences
Question 4519Question

In a fully automated logistics center, a single row of delivery robots is lined up facing the loading bay. Robot MM is positioned 27th27^{\text{th}} from the left end of the row, while Robot PP is positioned 31st31^{\text{st}} from the right end. If Robot MM and Robot PP interchange their positions, Robot PP becomes 48th48^{\text{th}} from the right end. Based on this rearrangement, what is the new position of Robot MM from the left end?

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Answer: 44th44^{\text{th}}

Answer

The new position of Robot M from the left end is the 44th44^{\text{th}} position.
The correct answer accurately synthesizes the overlapping ranks. By analyzing Robot P's new position (which is Robot M's old position), we find the total number of robots is 27+481=7427 + 48 - 1 = 74. Robot M moves to Robot P's old position, which is 31st31^{\text{st}} from the right. Its position from the left is then calculated as 7431+1=4474 - 31 + 1 = 44.

Step-by-Step Solution

1
Identify the coordinates of the interchange spot.
Robot PP moves to Robot MM's original spot. This spot is known to be 27th27^{\text{th}} from the left end. After the swap, we are told Robot PP is now 48th48^{\text{th}} from the right end.
Establishing both the left and right ranks for a single spot allows us to calculate the total number of entities in the sequence.
2
Calculate the total number of delivery robots (NN).
N=(Rank from Left)+(Rank from Right)1N = (\text{Rank from Left}) + (\text{Rank from Right}) - 1. Therefore, N=27+481=74N = 27 + 48 - 1 = 74 robots.
Adding the left and right ranks counts the robot sitting in that spot twice, so we must subtract 1 to get the accurate total count.
3
Identify Robot MM's new physical location.
Robot MM moves to Robot PP's original spot, which is stated as being 31st31^{\text{st}} from the right end.
To find Robot MM's rank from the left, we first need to isolate its exact rank from the right side.
4
Calculate Robot MM's new rank from the left end.
Rank from Left=N(Rank from Right)+1\text{Rank from Left} = N - (\text{Rank from Right}) + 1. Therefore, Rank = 7431+1=4474 - 31 + 1 = 44.
Subtracting the right rank from the total gives the number of robots to the left of Robot MM. Adding 1 includes Robot MM in the final positional count.

Key Concept

Positional Interchange and Total Sequence Capacity
Question 4520Question

Examine the policy details provided below and evaluate the logical validity of the subsequent inferences.

Policy Directives:
- Every public welfare initiative launched by the incumbent government mandates that recipients synchronize their national identity documents with their bank profiles to prevent fund misappropriation.
- The 'Urban Housing Assistance' framework is a newly launched public welfare initiative under the incumbent government.

Proposed Inferences:
I. Recipients of the 'Urban Housing Assistance' framework must synchronize their national identity documents with their bank profiles.
II. Welfare initiatives launched before the incumbent government experienced severe fund misappropriation.

Based exclusively on the policy directives provided, which inference can be logically deduced?

Show answer & explanation

Answer: Only inference I follows

Answer

Only inference I follows, as it is a direct application of the general rule to a specific case, whereas inference II assumes unstated historical facts.
The correct answer states that only inference I follows. The first policy directive establishes a universal rule: all welfare initiatives from the incumbent government require identity synchronization. The second directive establishes that the 'Urban Housing Assistance' framework falls into this exact category. Therefore, inference I is a valid deductive conclusion (Modus Ponens). Inference II, however, introduces historical context about prior governments that is not stated anywhere in the directives.

Step-by-Step Solution

1
Analyze the first policy directive to establish the general rule.
Rule: If a welfare initiative is launched by the incumbent government, recipients must synchronize their identity documents with bank profiles.
To understand the necessary conditions applied to new welfare initiatives.
2
Analyze the second policy directive to identify the specific case.
Case: 'Urban Housing Assistance' is a welfare initiative launched by the incumbent government.
To determine if the specific case falls under the general rule established in the first directive.
3
Evaluate Inference I against the established rule and case.
Since 'Urban Housing Assistance' fits the condition of the general rule, its recipients must synchronize their documents. Inference I is logically valid.
To test the logical deduction strictly based on provided facts.
4
Evaluate Inference II against the provided directives.
The first directive mentions the goal is 'to prevent fund misappropriation', but it does not explicitly state that prior initiatives suffered from 'severe' misappropriation. Inference II is an assumption, not a deduction.
To distinguish between explicitly stated facts and assumed historical context.

Key Concept

Statement and Conclusions or Inferences
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