Tüm alıştırma soruları

2131 soru

Soru 1921Soru

Although the committee chairman was initially revered for his uncompromising principles, subsequent archival discoveries revealed that his public stance had been largely ______ , calculated more to cultivate a pious reputation than to express genuine moral conviction.

Which TWO of the following words, when inserted into the blank, produce sentences that are equivalent in meaning?

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Cevap: sanctimonious; hypocritical

Cevap

The words 'sanctimonious' and 'hypocritical' complete the sentence by creating logically coherent and equivalent sentences.
The sentence contrasts the chairman's public reputation for uncompromising principles with the reality that his stance was motivated by a desire to appear devout without holding genuine conviction. The terms 'sanctimonious' and 'hypocritical' both describe a false or affected display of virtue and moral superiority, ensuring that both selections result in sentences with identical meaning.

Adım Adım Çözüm

1
Analyze structural pivots and sentence context
The opening transition 'Although' signals a shift between the chairman's perceived 'uncompromising principles' and the reality. The clause 'calculated more to cultivate a pious reputation than to express genuine moral conviction' indicates that the blank must describe false, insincere, or affected moral uprightness.
Identifying the target tone and meaning required to complete the contrast setup.
2
Evaluate candidate words for contextual fit
'Sanctimonious' (making a show of being morally superior or pious) and 'hypocritical' (insincerely professing virtues one does not possess) both accurately fill the blank.
Both words match the requirement of insincere moral pretense.
3
Verify pair equivalence and eliminate distractors
'Sanctimonious' and 'hypocritical' form a valid near-synonym pair in this context. While 'austere' and 'spartan' form a synonym pair, they mean strict/severe and fail contextual fit. 'Disingenuous' fits context individually but lacks a synonym partner. 'Pious' creates a logical contradiction.
Sentence Equivalence requires selecting two words that produce identical overall sentence meanings.

Anahtar Kavram

Identifying Synonym and Near-Synonym Pairs in Context
Soru 1922Soru

An agricultural cooperative harvested crops from three distinct farming zones: Zone A, Zone B, and Zone C. In Season 1, Zone A accounted for 40%40\% of the cooperative's total crop yield, Zone B accounted for 35%35\%, and Zone C accounted for the remaining 25%25\%.

In Season 2:
- The crop yield in Zone A increased by 15%15\% compared to Season 1.
- The crop yield in Zone B decreased by 20%20\% compared to Season 1.
- The crop yield in Zone C increased by p%p\% compared to Season 1.

If the cooperative's total crop yield in Season 2 was 6%6\% greater than its total crop yield in Season 1, what is the value of pp?

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Cevap: 28

Cevap

The value of pp is 2828.
The correct value of pp is 2828. Calculating the weighted percentage contributions of each zone shows that Zone A contributes a yield equal to 46%46\% of the original total yield and Zone B contributes 28%28\%, making their combined Season 2 contribution 74%74\% of the original total yield. To reach the required total Season 2 yield of 106%106\% of the original total, Zone C must contribute 106%74%=32%106\% - 74\% = 32\% of the original total yield. Since Zone C initially produced 25%25\% of the total yield, the percentage increase for Zone C is 322525×100%=725×100%=28%\frac{32 - 25}{25} \times 100\% = \frac{7}{25} \times 100\% = 28\%.

Adım Adım Çözüm

1
Define total initial yield and express Season 1 yields for each zone in terms of total yield YY.
Zone A yield = 0.40Y0.40Y, Zone B yield = 0.35Y0.35Y, Zone C yield = 0.25Y0.25Y.
Establishing baseline values based on given initial percentage shares.
2
Calculate the Season 2 yields for Zones A and B after their respective percentage changes.
Zone A yield in Season 2 = 0.40Y×1.15=0.46Y0.40Y \times 1.15 = 0.46Y. Zone B yield in Season 2 = 0.35Y×0.80=0.28Y0.35Y \times 0.80 = 0.28Y.
Applying a 15% increase to Zone A and a 20% decrease to Zone B.
3
Set up the total Season 2 yield equation using the given 6% overall increase.
0.46Y+0.28Y+0.25Y(1+p100)=1.06Y0.46Y + 0.28Y + 0.25Y\left(1 + \frac{p}{100}\right) = 1.06Y.
The sum of all three zone yields in Season 2 equals 106% of the total Season 1 yield.
4
Solve for pp.
0.74+0.25(1+p100)=1.06    0.25(1+p100)=0.32    1+p100=1.28    p=280.74 + 0.25\left(1 + \frac{p}{100}\right) = 1.06 \implies 0.25\left(1 + \frac{p}{100}\right) = 0.32 \implies 1 + \frac{p}{100} = 1.28 \implies p = 28.
Subtracting 0.74 from 1.06 gives 0.32, and dividing 0.32 by 0.25 yields 1.28, representing a 28% increase.

Anahtar Kavram

Weighted Percent Change and Base Values
Soru 1923Soru

A craft brewery blends two batches of cider. Batch A contains a 12%12\% sugar solution by volume, and Batch B contains a 20%20\% sugar solution by volume. The brewer mixes 1515 liters of Batch A with xx liters of Batch B to create a resulting mixture that is 17%17\% sugar by volume. What is the value of xx?

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Cevap: 25

Cevap

The value of xx is 2525.
Equating the total amount of pure sugar before and after mixing gives 0.12(15)+0.20x=0.17(15+x)0.12(15) + 0.20x = 0.17(15 + x). Simplifying yields 1.8+0.20x=2.55+0.17x1.8 + 0.20x = 2.55 + 0.17x, which reduces to 0.03x=0.750.03x = 0.75, giving x=25x = 25.

Adım Adım Çözüm

1
Calculate the volume of pure sugar contributed by Batch A
0.12×15=1.80.12 \times 15 = 1.8 liters of pure sugar
Batch A is 12%12\% sugar by volume and has a total volume of 1515 liters.
2
Express the total volume of pure sugar in terms of xx
Total sugar volume = 1.8+0.20x1.8 + 0.20x liters
Batch B adds xx liters of a 20%20\% sugar solution.
3
Set up the mixture equation
1.8+0.20x=0.17(15+x)1.8 + 0.20x = 0.17(15 + x)
The final mixture has a total volume of (15+x)(15 + x) liters with a concentration of 17%17\% sugar.
4
Expand and solve the linear equation for xx
1.8+0.20x=2.55+0.17x    0.03x=0.75    x=251.8 + 0.20x = 2.55 + 0.17x \implies 0.03x = 0.75 \implies x = 25
Subtract 0.17x0.17x and 1.81.8 from both sides, then divide by 0.030.03.

Anahtar Kavram

Linear Equations in One Variable (Mixture Word Problems)
Tahmini Süre:1m 30s
Soru 1924Soru

For all real numbers xx such that x5x \neq 5, which of the following expressions is equivalent to x2253x15\frac{x^2 - 25}{3x - 15}?

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Cevap: x+53\frac{x + 5}{3}

Cevap

The expression x+53\frac{x + 5}{3} is equivalent to the given rational expression for all x5x \neq 5.
Factoring the numerator as a difference of squares gives (x5)(x+5)(x - 5)(x + 5), and factoring the denominator gives 3(x5)3(x - 5). Dividing out the common factor (x5)(x - 5) simplifies the expression to x+53\frac{x + 5}{3}.

Adım Adım Çözüm

1
Factor the numerator using the difference of squares identity.
x225=(x5)(x+5)x^2 - 25 = (x - 5)(x + 5)
The difference of squares a2b2a^2 - b^2 factors into (ab)(a+b)(a - b)(a + b).
2
Factor out the greatest common factor from the denominator.
3x15=3(x5)3x - 15 = 3(x - 5)
Both terms in 3x153x - 15 share a common factor of 33.
3
Divide out the common binomial factor (x5)(x - 5) from the numerator and denominator.
(x5)(x+5)3(x5)=x+53\frac{(x - 5)(x + 5)}{3(x - 5)} = \frac{x + 5}{3}
Since x5x \neq 5, the factor (x5)(x - 5) is non-zero and can be cancelled.

Anahtar Kavram

Simplifying rational algebraic expressions by factoring difference of squares and common linear factors.
Soru 1925Soru

An industrial laboratory prepares a batch of Alloy ZZ weighing 260260 pounds, which consists solely of copper and zinc in a ratio of 7:67 : 6 by weight. A technician then adds 4040 pounds of pure copper to this batch to create Alloy WW. What is the ratio of copper to zinc in Alloy WW?

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Cevap: 3 : 2

Cevap

3 : 2
In Alloy Z, the total weight of 260 pounds is divided into 13 equal parts of 20 pounds each. Thus, copper accounts for 7 parts (140 pounds) and zinc accounts for 6 parts (120 pounds). Adding 40 pounds of pure copper increases the copper content to 180 pounds, while zinc remains at 120 pounds. Comparing copper to zinc yields 180 : 120, which simplifies to 3 : 2.

Adım Adım Çözüm

1
Determine total ratio parts for Alloy Z.
The total number of ratio parts is 7+6=137 + 6 = 13 parts.
To find the weight of each component from a part-to-part ratio, divide the total weight by total ratio parts.
2
Calculate initial weights of copper and zinc in Alloy Z.
Copper weight =260×713=140= 260 \times \frac{7}{13} = 140 pounds; Zinc weight =260×613=120= 260 \times \frac{6}{13} = 120 pounds.
Multiply total weight by each component's fraction of the total.
3
Update component weights after adding pure copper.
New copper weight =140+40=180= 140 + 40 = 180 pounds; Zinc weight remains 120120 pounds.
Only copper is added to the mixture, leaving zinc weight unchanged.
4
Compute and simplify the final ratio of copper to zinc for Alloy W.
Ratio of copper to zinc =180:120=3:2= 180 : 120 = 3 : 2.
Divide both terms by their greatest common divisor, 60.

Anahtar Kavram

Ratios and Component Mixture Adjustment
Soru 1926Soru

Read the following passage regarding early modern scientific methodology:

In his reevaluation of early modern scientific methodology, historian Julian Vance does not outright reject the traditional narrative that empirical observation abruptly supplanted scholasticism; rather, he seeks to qualify it. By emphasizing that late medieval scholars frequently engaged in systematic observational practices long before the Scientific Revolution, Vance demonstrates that the transition was incremental rather than revolutionary, thereby refining overly simplistic historical assertions.

In the context of the passage, which of the following best captures the meaning of the word "qualify"?

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Cevap: limit or moderate the scope of

Cevap

In the context of the passage, the word 'qualify' means to limit or moderate the scope of a statement or claim.
The sentence employs a negative-contrast structure: 'does not outright reject... rather, he seeks to qualify it.' The signal 'rather' alongside the clarification that Vance refines 'overly simplistic assertions' demonstrates that 'qualify' carries its secondary academic definition of modifying, limiting, or moderating a claim.

Adım Adım Çözüm

1
Analyze the structural pivot marker
Identified the contrast construction: 'does not outright reject [X]; rather, he seeks to [target word] it.'
The transition signal 'rather' indicates a shift to an action that lies between total rejection and complete acceptance.
2
Examine the elaboration in the subsequent sentence
The text explains that Vance shows the shift was 'incremental rather than revolutionary' to refine 'overly simplistic historical assertions.'
This elaboration demonstrates that Vance is adjusting and restricting the boundaries of the traditional claim rather than abandoning it or accepting it as originally stated.
3
Match contextual meaning with option choices
Selected the option meaning 'limit or moderate the scope of'.
Secondary definitions of 'qualify' include to modify, limit, or restrict a statement, perfectly aligning with the structural context.

Anahtar Kavram

Deciphering secondary word meanings using contrast transition signals and clause relationships
Soru 1927Soru

Read the passage below and complete the sentence by providing the word that best fits the blank based on the structural clues and contrast signals.

Aşağıdaki boşlukları doldurun

In nineteenth-century historiography of the Ancient Near East, early scholars categorized Bronze Age administrative tablets as strictly matter-of-fact record-keeping tools. Far from being merely ledgers of grain distribution and livestock inventories, however, recent epigraphic decipherments demonstrate that these inscriptions were crafted with subtle rhetorical flourishes designed to reinforce royal lineage and divine legitimacy.
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Cevap

The word that best completes the blank is 'prosaic' (or synonymous terms such as 'mundane', 'pedestrian', or 'utilitarian').
The correct response requires recognizing the structural contrast signaled by 'Far from being merely {{blank_1}}... however'. The first sentence characterizes early scholarship's view of the tablets as 'strictly matter-of-fact record-keeping tools.' The second sentence introduces new findings showing the tablets contained 'subtle rhetorical flourishes' promoting 'divine legitimacy.' The missing word must therefore describe ledgers that are commonplace, unadorned, or purely functional—making words like 'prosaic', 'mundane', 'pedestrian', or 'utilitarian' contextually precise.

Adım Adım Çözüm

1
Identify the primary context and initial descriptor.
The initial sentence establishes that early scholars viewed the administrative tablets as 'strictly matter-of-fact record-keeping tools.'
This establishes the initial baseline concept against which the rest of the sentence will react.
2
Analyze the structural signals and transition markers.
The clause begins with the concessive/contrast signal 'Far from being merely...' and is reinforced by the contrast pivot marker 'however'.
These signals signal a sharp opposition between the traditional expectation of the ledgers and the actual discovery of 'subtle rhetorical flourishes' and 'divine legitimacy.'
3
Deduce the required tone and definition for the blank.
The word filling the blank must align with 'matter-of-fact' and contrast with 'rhetorical flourishes.' It must convey that the ledgers were ordinary, uninspired, or purely functional.
Selecting 'prosaic', 'mundane', or 'utilitarian' completes the contrast created by the structural pivot.

Anahtar Kavram

Deciphering Meaning via Structural Clues and Contrast/Continuation Signals
Tahmini Süre:1m 15s
Soru 1928Soru

Read the passage below. Determine which terms best complete each corresponding blank to maintain cross-sentence contextual coherence.

Aşağıdaki boşlukları doldurun

For decades, ethnoarchaeologists believed that ancient low-temperature pottery firing was entirely , assuming that early potters lacked precise temperature control mechanisms. However, recent thermal analysis of ceramic vitrification reveals that these artisans utilized subtle draft adjustments to achieve astonishingly internal temperatures across separate firings. Consequently, scholars have begun to earlier characterizations of prehistoric pyrotechnology as rudimentary.
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Cevap

Blank (i): unpredictable; Blank (ii): consistent; Blank (iii): reconsider
The initial sentence establishes an assumption of primitive, uncontrolled technology, making 'unpredictable' the appropriate choice for the first blank. The transition word 'However' introduces contradictory empirical evidence demonstrating precise thermal regulation, requiring 'consistent' for the second blank. Finally, 'Consequently' signals a logical shift in academic consensus resulting from this finding, necessitating 'reconsider' for the third blank.

Adım Adım Çözüm

1
Analyze the structural and semantic clues in the first sentence.
The clause 'assuming that early potters lacked precise temperature control mechanisms' establishes that scholars viewed the firing outcomes as erratic, supporting 'unpredictable'.
The blank must reflect an outcome resulting from a lack of control mechanisms.
2
Identify the contrast signal introducing the second sentence.
The discourse marker 'However' indicates a pivot away from the traditional view, showing that 'subtle draft adjustments' produced stable heat levels, requiring 'consistent'.
The finding refutes the assumption of unpredictability by demonstrating thermal control.
3
Evaluate the logical consequence indicated in the final sentence.
The transition 'Consequently' signals that the newly demonstrated technological skill forces researchers to reassess old beliefs, necessitating 'reconsider'.
Evidence of sophisticated craft control directly undermines earlier claims that the technology was rudimentary.

Anahtar Kavram

Cross-Sentence Contextual Coherence in Multi-Blank Text Completion
Tahmini Süre:1m 30s
Soru 1929Soru

Let n=2a3bpcn = 2^a \cdot 3^b \cdot p^c, where aa, bb, and cc are positive integers and pp is a prime number strictly greater than 55. The integer nn has exactly 3636 positive divisors, and gcd(n,180)=36\gcd(n, 180) = 36. Which of the following statements MUST be true? Select all such statements.

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Cevap: The integer nn is divisible by 3636.; The exponent cc cannot exceed 33.; The least common multiple of nn and 180180 is equal to 5n5n.

Cevap

The statements asserting that nn is divisible by 3636, that the exponent cc cannot exceed 33, and that lcm(n,180)=5n\text{lcm}(n, 180) = 5n must be true.
The statement that nn is divisible by 3636 is true because a2a \ge 2 and b2b \ge 2. The statement that c3c \le 3 is true because (a+1)(b+1)9(a+1)(b+1) \ge 9, bounding c+14c+1 \le 4. The statement that lcm(n,180)=5n\text{lcm}(n, 180) = 5n is true because max(a,2)=a\max(a, 2) = a, max(b,2)=b\max(b, 2) = b, and 180180 contributes a factor of 515^1.

Adım Adım Çözüm

1
Analyze the GCD condition to establish bounds on exponents aa and bb.
a2a \ge 2 and b2b \ge 2.
Since 180=223251180 = 2^2 \cdot 3^2 \cdot 5^1 and gcd(n,180)=36=2232\gcd(n, 180) = 36 = 2^2 \cdot 3^2, the minimum of the exponents of 22 is 22 (so a2a \ge 2) and the minimum of the exponents of 33 is 22 (so b2b \ge 2).
2
Use the divisor count formula (a+1)(b+1)(c+1)=36(a+1)(b+1)(c+1) = 36 to find constraints on cc.
c3c \le 3.
Since a2    a+13a \ge 2 \implies a+1 \ge 3 and b2    b+13b \ge 2 \implies b+1 \ge 3, the product (a+1)(b+1)9(a+1)(b+1) \ge 9. Therefore, c+1=36(a+1)(b+1)369=4c+1 = \frac{36}{(a+1)(b+1)} \le \frac{36}{9} = 4, which gives c3c \le 3.
3
Evaluate the divisibility of nn by 3636.
nn is divisible by 3636.
Because a2a \ge 2 and b2b \ge 2, 2232=362^2 \cdot 3^2 = 36 divides 2a3bpc=n2^a \cdot 3^b \cdot p^c = n.
4
Calculate lcm(n,180)\text{lcm}(n, 180).
lcm(n,180)=5n\text{lcm}(n, 180) = 5n.
lcm(2a3bpc,223251)=2max(a,2)3max(b,2)51pc=2a3b5pc=5n\text{lcm}(2^a \cdot 3^b \cdot p^c, 2^2 \cdot 3^2 \cdot 5^1) = 2^{\max(a,2)} \cdot 3^{\max(b,2)} \cdot 5^1 \cdot p^c = 2^a \cdot 3^b \cdot 5 \cdot p^c = 5n since a2a \ge 2, b2b \ge 2, and p>5p > 5.
5
Test counterexamples for statement constancy regarding a+b+c=7a+b+c=7 and a=2a=2.
Neither a+b+c=7a+b+c=7 nor a=2a=2 is required.
The choice (a,b,c)=(5,2,1)(a, b, c) = (5, 2, 1) satisfies (5+1)(2+1)(1+1)=36(5+1)(2+1)(1+1) = 36 and gcd(n,180)=36\gcd(n, 180) = 36, yielding a+b+c=87a+b+c=8 \neq 7 and a=52a=5 \neq 2.

Anahtar Kavram

Prime Factorization, Greatest Common Divisor (GCD), and Least Common Multiple (LCM) properties
Soru 1930Soru

Rather than viewing the archivist's uncatalogued personal diaries as (i)________ reflections of trivial personal matters, recent historians contend that these candid entries provide an indispensable window into the era's broader socio-political currents; nevertheless, the diaries' fragmented nature requires scholars to exercise considerable (ii)________ when drawing sweeping structural conclusions.

Which pair of word choices best completes the passage?

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Cevap: (i) parochial, (ii) circumspection

Cevap

The pair '(i) parochial, (ii) circumspection' logically completes the passage.
The correct option pairs 'parochial' with 'circumspection'. The initial contrast signal 'Rather than viewing...' sets up an opposition between the traditional view of the diaries as narrow or limited ('parochial') and the modern view of them as illuminating broad historical trends. The secondary pivot 'nevertheless' introduces a qualification: because the diaries are 'fragmented', historians must exercise prudence and caution ('circumspection') when drawing broad conclusions.

Adım Adım Çözüm

1
Analyze the structural pivot for Blank (i)
The opening phrase 'Rather than viewing... as (i)______ reflections of trivial personal matters, recent historians contend that... broader socio-political currents' creates a direct contrast between the old perception (narrow/small-scale) and the new historical perspective (broad/significant).
Blank (i) must mean narrow, limited, or provincial to mirror 'trivial personal matters' and contrast with 'broader socio-political currents'.
2
Evaluate candidates for Blank (i)
'Parochial' means limited or narrow in scope, which fits the contrast perfectly. 'Profound' is the opposite of trivial, breaking the contrast. 'Tendentious' means biased, which is not supported by the context of triviality.
Only 'parochial' establishes the required semantic valence for Blank (i).
3
Analyze the structural pivot for Blank (ii) based on Blank (i) and passage context
The semicolon followed by 'nevertheless' signals a concession. Even though the diaries offer valuable broad insights, their 'fragmented nature' demands that scholars proceed with care.
Blank (ii) requires a noun meaning prudence, care, or caution when forming sweeping conclusions from incomplete data.
4
Evaluate candidates for Blank (ii) and verify joint alignment
'Circumspection' means caution and prudence, perfectly matching the warning about 'fragmented nature'. 'Temerity' (foolhardy boldness) and 'apathy' (lack of interest) fail contextually.
Combining 'parochial' for Blank (i) and 'circumspection' for Blank (ii) satisfies both local syntax and inter-blank logical dependency.

Anahtar Kavram

Multi-Blank Dependency Tracking
Tahmini Süre:1m 30s
Soru 1931Soru

On the real number line, points PP, QQ, and RR have coordinates xx, yy, and zz, respectively, such that x2=5|x - 2| = 5, y+4=3|y + 4| = 3, and zz is the midpoint of segment PQPQ. If x<yx < y, what is the value of zz?

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Cevap: -2

Cevap

The coordinate of point RR (the value of zz) is 2-2.
Solving the two absolute value equations yields x{3,7}x \in \{-3, 7\} and y{7,1}y \in \{-7, -1\}. Testing the given constraint x<yx < y across all four possible ordered pairs reveals that only x=3x = -3 and y=1y = -1 satisfy the condition, since 3<1-3 < -1 is true while all other pairs fail. The midpoint of points with coordinates 3-3 and 1-1 is 3+(1)2=2\frac{-3 + (-1)}{2} = -2.

Adım Adım Çözüm

1
Solve the absolute value equation x2=5|x - 2| = 5.
x=7x = 7 or x=3x = -3
The equation x2=5|x - 2| = 5 splits into x2=5    x=7x - 2 = 5 \implies x = 7 and x2=5    x=3x - 2 = -5 \implies x = -3.
2
Solve the absolute value equation y+4=3|y + 4| = 3.
y=1y = -1 or y=7y = -7
The equation y+4=3|y + 4| = 3 splits into y+4=3    y=1y + 4 = 3 \implies y = -1 and y+4=3    y=7y + 4 = -3 \implies y = -7.
3
Evaluate all candidate pairs (x,y)(x, y) under the inequality constraint x<yx < y.
The only valid pair is x=3x = -3 and y=1y = -1.
Comparing all four combinations: 7<17 < -1 (false), 7<77 < -7 (false), 3<7-3 < -7 (false), and 3<1-3 < -1 (true).
4
Calculate the midpoint zz of the segment PQPQ.
z=2z = -2
The midpoint of coordinates 3-3 and 1-1 on a number line is given by their average: 3+(1)2=2\frac{-3 + (-1)}{2} = -2.

Anahtar Kavram

Absolute Value Equations and Midpoint on the Real Number Line
Soru 1932Soru

If 3x+3x=43^x + 3^{-x} = 4, what is the value of 27x+27x29x+9x+1\frac{27^x + 27^{-x} - 2}{9^x + 9^{-x} + 1}?

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Cevap: 103\frac{10}{3}

Cevap

103\frac{10}{3}
Squaring 3x+3x=43^x + 3^{-x} = 4 yields 9x+2+9x=169^x + 2 + 9^{-x} = 16, which simplifies to 9x+9x=149^x + 9^{-x} = 14. Utilizing the sum of cubes identity gives 27x+27x=(3x+3x)(9x1+9x)=4(141)=5227^x + 27^{-x} = (3^x + 3^{-x})(9^x - 1 + 9^{-x}) = 4(14 - 1) = 52. Substituting these values into the given fraction gives 52214+1=5015=103\frac{52 - 2}{14 + 1} = \frac{50}{15} = \frac{10}{3}.

Adım Adım Çözüm

1
Square the given expression 3x+3x=43^x + 3^{-x} = 4 to determine 9x+9x9^x + 9^{-x}.
(3x+3x)2=9x+2(3x)(3x)+9x=9x+2+9x=16(3^x + 3^{-x})^2 = 9^x + 2(3^x)(3^{-x}) + 9^{-x} = 9^x + 2 + 9^{-x} = 16, which yields 9x+9x=149^x + 9^{-x} = 14.
Expanding the square of a binomial requires accounting for the middle term 23x3x=22 \cdot 3^x \cdot 3^{-x} = 2.
2
Express 27x+27x27^x + 27^{-x} using the sum of cubes factorization identity.
27x+27x=(3x)3+(3x)3=(3x+3x)(9x3x3x+9x)=4(141)=5227^x + 27^{-x} = (3^x)^3 + (3^{-x})^3 = (3^x + 3^{-x})(9^x - 3^x \cdot 3^{-x} + 9^{-x}) = 4(14 - 1) = 52.
The identity a3+b3=(a+b)(a2ab+b2)a^3 + b^3 = (a + b)(a^2 - ab + b^2) allows factoring cubic exponential expressions.
3
Substitute the evaluated terms into the target rational expression and simplify.
\frac{27^x + 27^{-x} - 2}{9^x + 9^{-x} + 1} = \frac{52 - 2}{14 + 1} = \frac{50}{15} = \frac{10}{3}.
Replacing component expressions with their computed values yields the simplified numerical fraction.

Anahtar Kavram

Evaluating high-power exponential expressions using polynomial identity transformations and exponent laws.
Soru 1933Soru

Far from being an intentional __________ of the empirical record, the climatologist’s understated projections regarding sea-level rise reflected a conservative methodology designed to minimize speculative risk rather than a deliberate attempt to mislead the public. Which two of the following answer choices, when inserted into the sentence, produce completed sentences that are identical in meaning?

Geçerli olan tümünü seçin

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Cevap: distortion; falsification

Cevap

distortion and falsification
The sentence specifies that the climatologist's understated projections were not a 'deliberate attempt to mislead the public.' Therefore, the blank requires words meaning intentional misrepresentation or alteration of facts. The words 'distortion' and 'falsification' both accurately convey this meaning, and substituting either into the sentence yields completed sentences with identical meaning.

Adım Adım Çözüm

1
Analyze structural clues and contrast signals in the sentence stem.
The phrase 'rather than a deliberate attempt to mislead' indicates that the blank must mean a deliberate misrepresentation, altering, or faking of data.
The contrast structure 'Far from being an intentional [blank]... reflected a conservative methodology... rather than a deliberate attempt to mislead' demands a word denoting deceptive alteration of facts.
2
Evaluate option pairs for semantic equivalence in context.
'distortion' and 'falsification' both mean altering or misrepresenting empirical data to mislead, creating equivalent sentence meanings.
Both words fit the contextual requirement of dishonest data manipulation and produce sentences with identical overall meaning.
3
Identify false synonym traps and topically related distractors.
'exaggeration' and 'hyperbole' form a valid synonym pair but fail contextually because the projections were 'understated' (overstatement contradicts the context). 'revision' and 'precision' are topically relevant scientific terms but lack synonymous partners.
Eliminating false synonym pairs that fail context and unpaired topical distractors yields the unique correct answer pair.

Anahtar Kavram

Eliminating False Synonyms and Topically Related Distractors
Soru 1934Soru

Two positive integers xx and yy satisfy x<yx < y, gcd(x,y)=18\gcd(x, y) = 18, and lcm(x,y)=1080\text{lcm}(x, y) = 1080. If xx has exactly 66 positive divisors, what is the value of yy?

Cevabı ve açıklamayı göster

Cevap: 10801080

Cevap

1080
Since gcd(x,y)=18\gcd(x, y) = 18 and lcm(x,y)=1080\text{lcm}(x, y) = 1080, we can express x=18mx = 18m and y=18ny = 18n with gcd(m,n)=1\gcd(m, n) = 1 and m<nm < n. Substituting into lcm(x,y)=18mn=1080\text{lcm}(x, y) = 18mn = 1080 gives mn=60mn = 60. The coprime pairs (m,n)(m, n) with m<nm < n are (1,60)(1, 60), (3,20)(3, 20), (4,15)(4, 15), and (5,12)(5, 12). Testing x=18mx = 18m for each pair: for m=1m = 1, x=18=2132x = 18 = 2^1 \cdot 3^2, which has (1+1)(2+1)=6(1+1)(2+1) = 6 positive divisors. This matches the condition, so n=60n = 60 and y=18×60=1080y = 18 \times 60 = 1080.

Adım Adım Çözüm

1
Express xx and yy in terms of their Greatest Common Divisor
Let x=18mx = 18m and y=18ny = 18n, where mm and nn are positive integers such that m<nm < n and gcd(m,n)=1\gcd(m, n) = 1.
Since gcd(x,y)=18\gcd(x, y) = 18, both numbers must be multiples of 1818, and their remaining factor parts must be coprime.
2
Use the LCM formula lcm(x,y)=18mn\text{lcm}(x, y) = 18mn to find mnmn
18mn=1080    mn=6018mn = 1080 \implies mn = 60.
The least common multiple of 18m18m and 18n18n with gcd(m,n)=1\gcd(m,n)=1 is 18mn18mn.
3
Find all coprime factor pairs (m,n)(m, n) of 6060 with m<nm < n
The prime factorization of 6060 is 2231512^2 \cdot 3^1 \cdot 5^1. Coprime pairs (m,n)(m, n) are (1,60)(1, 60), (3,20)(3, 20), (4,15)(4, 15), and (5,12)(5, 12).
Pairs must be coprime so that gcd(18m,18n)=18\gcd(18m, 18n) = 18 remains true.
4
Determine the number of positive divisors for x=18mx = 18m for each candidate pair
For m=1m = 1, x=18=2132x = 18 = 2^1 \cdot 3^2, which has (1+1)(2+1)=6(1+1)(2+1) = 6 positive divisors.
The number of positive divisors of p1a1p2a2p_1^{a_1} p_2^{a_2} \dots is given by (a1+1)(a2+1)(a_1 + 1)(a_2 + 1) \dots. Only m=1m = 1 gives exactly 66 divisors.
5
Calculate yy
y=18n=1860=1080y = 18n = 18 \cdot 60 = 1080.
Corresponding to m=1m = 1, n=60n = 60 gives y=1080y = 1080.

Anahtar Kavram

Prime Factorization, GCD/LCM Coprime Relationships, and Divisor Counting Formula

Alternatif Yöntem

Alternatively, use gcd(x,y)lcm(x,y)=xy    xy=181080=19440\gcd(x, y) \cdot \text{lcm}(x, y) = x \cdot y \implies x \cdot y = 18 \cdot 1080 = 19440. Since xx has 66 positive divisors and xx is a multiple of 1818, xx must equal 1818 because 18=213218 = 2^1 \cdot 3^2 has (1+1)(2+1)=6(1+1)(2+1) = 6 divisors. Then y=19440/18=1080y = 19440 / 18 = 1080.
Tahmini Süre:1m 30s
Soru 1935Soru

In trapezoid ABCDABCD, side ABAB is parallel to side CDCD, and DAB=90\angle DAB = 90^\circ. If AB=14AB = 14, CD=8CD = 8, and BC=10BC = 10, what is the area of trapezoid ABCDABCD?

Cevabı ve açıklamayı göster

Cevap: 88

Cevap

88
By drawing an altitude from point CC perpendicular to base ABAB at point HH, the trapezoid is partitioned into a rectangle ADCHADCH and a right triangle CHBCHB. The base of triangle CHBCHB is HB=148=6HB = 14 - 8 = 6, and its hypotenuse is BC=10BC = 10. Applying the Pythagorean theorem yields CH=10262=8CH = \sqrt{10^2 - 6^2} = 8. Using the trapezoid area formula b1+b22×h\frac{b_1 + b_2}{2} \times h gives 14+82×8=88\frac{14 + 8}{2} \times 8 = 88.

Adım Adım Çözüm

1
Decompose the trapezoid into a rectangle and a right triangle.
Draw a line segment from vertex CC perpendicular to base ABAB, intersecting ABAB at point HH. Quadrilateral ADCHADCH is a rectangle, and triangle CHBCHB is a right triangle with right angle at HH.
Splitting the trapezoid allows the perpendicular height to be determined using right triangle properties.
2
Determine the horizontal base of right triangle CHBCHB.
Since ADCHADCH is a rectangle, AH=CD=8AH = CD = 8. Therefore, HB=ABAH=148=6HB = AB - AH = 14 - 8 = 6.
Opposite sides of a rectangle are equal in length.
3
Calculate height CHCH using the Pythagorean theorem.
In right triangle CHBCHB, CH2+HB2=BC2    CH2+62=102    CH2+36=100    CH=64=8CH^2 + HB^2 = BC^2 \implies CH^2 + 6^2 = 10^2 \implies CH^2 + 36 = 100 \implies CH = \sqrt{64} = 8.
The height of the trapezoid corresponds to leg CHCH of right triangle CHBCHB.
4
Calculate the area of trapezoid ABCDABCD.
\text{Area} = \frac{AB + CD}{2} \times CH = \frac{14 + 8}{2} \times 8 = 11 \times 8 = 88.
The area formula for a trapezoid is half the sum of the parallel bases multiplied by the perpendicular height.

Anahtar Kavram

Decomposing a trapezoid into a rectangle and a right triangle to calculate height via the Pythagorean theorem
Tahmini Süre:1m 15s
Soru 1936Soru

A technology startup recorded the monthly software subscription costs, in dollars, for 6 department teams: 450,120,310,120,280,450, 120, 310, 120, 280, and 500500. A seventh department team with a monthly subscription cost of xx dollars is added to the dataset, where xx is a positive integer. Which of the following statements regarding the measures of central tendency for the updated 7-team dataset must be true? Select all that apply.

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Cevap: The median of the subscription costs for the 7 teams cannot be greater than 310.; If x=600x = 600, the arithmetic mean of the subscription costs for the 7 teams is greater than the median.

Cevap

The statements that must be true are that the median cannot exceed 310, and that if x = 600, the arithmetic mean is greater than the median.
Sorting the six known values gives 120, 120, 280, 310, 450, 500. In a dataset of 7 numbers, the median is the 4th value when sorted. If x is added, the 4th value will be 280 if x ≤ 280, x if 280 < x < 310, or 310 if x ≥ 310. Thus, the median is capped at 310. Furthermore, setting x = 600 yields a median of 310 and a mean of (1780 + 600) / 7 = 340, which is greater than the median.

Adım Adım Çözüm

1
Sort the existing 6 dataset elements in ascending order and compute their sum.
Sorted list: 120, 120, 280, 310, 450, 500. Sum = 1780.
Establishing the baseline position of values helps determine how inserting x shifts the median, mean, and mode.
2
Analyze the position of the median for a 7-element dataset.
The median is the 4th element when sorted. If x ≤ 280, the 4th element is 280. If 280 < x < 310, the 4th element is x. If x ≥ 310, the 4th element is 310. Thus, 280 ≤ median ≤ 310.
This establishes upper and lower bounds for the median regardless of x.
3
Evaluate the statement regarding median upper bound (median ≤ 310).
Since the maximum possible 4th element in the sorted 7-element list is 310, the median can never be greater than 310.
Confirms the validity of the statement concerning the maximum median.
4
Evaluate the scenario where x = 600.
Sum = 1780 + 600 = 2380. Mean = 2380 / 7 = 340. Median = 310 (since 600 ≥ 310). 340 > 310.
Confirms that when x = 600, mean (340) is strictly greater than median (310).

Anahtar Kavram

Measures of Central Tendency (Mean, Median, Mode)
Soru 1937Soru

In Year 1, a technology firm allocated 40%40\% of its total operating budget to Research and Development (R&D) and the remaining 60%60\% to Business Operations. In Year 2, the amount allocated to R&D was increased by 25%25\% over its Year 1 amount, while the amount allocated to Business Operations was decreased by 15%15\% from its Year 1 amount. If the firm's total operating budget in Year 2 was $505,000\$505,000, what was its total operating budget in Year 1?

Cevabı ve açıklamayı göster

Cevap: $500,000\$500,000

Cevap

The total operating budget in Year 1 was $500,000\$500,000.
The budget allocation in Year 1 assigns 40%40\% to R&D and 60%60\% to Operations. In Year 2, R&D becomes 0.40×1.25=0.500.40 \times 1.25 = 0.50 of the Year 1 budget, and Operations becomes 0.60×0.85=0.510.60 \times 0.85 = 0.51 of the Year 1 budget. Adding these yields a Year 2 total equal to 1.011.01 times the Year 1 budget. Setting 1.01×Year 1 Budget=$505,0001.01 \times \text{Year 1 Budget} = \$505,000 and dividing gives $500,000\$500,000.

Adım Adım Çözüm

1
Define Year 1 components in terms of total Year 1 budget BB.
R&D allocation = 0.40B0.40B; Operations allocation = 0.60B0.60B.
The problem specifies a 40%/60%40\% / 60\% split of the total budget BB in Year 1.
2
Calculate Year 2 allocations after percentage changes.
Year 2 R&D = 0.40B×1.25=0.50B0.40B \times 1.25 = 0.50B; Year 2 Operations = 0.60B×0.85=0.51B0.60B \times 0.85 = 0.51B.
R&D increases by 25%25\% (1+0.25=1.251 + 0.25 = 1.25) and Operations decreases by 15%15\% (10.15=0.851 - 0.15 = 0.85).
3
Sum Year 2 allocations to express total Year 2 budget in terms of BB.
Total Year 2 Budget = 0.50B+0.51B=1.01B0.50B + 0.51B = 1.01B.
Combining both component allocations gives the total budget for Year 2.
4
Solve for the Year 1 budget BB using the given Year 2 total.
1.01B=$505,000    B=505,0001.01=$500,0001.01B = \$505,000 \implies B = \frac{505,000}{1.01} = \$500,000.
Dividing the Year 2 budget by the total growth multiplier yields the original Year 1 budget.

Anahtar Kavram

Weighted Percent Change and Initial Base Calculation
Soru 1938Soru

In the xyxy-plane, line kk passes through the points (6,0)(-6, 0) and (0,4)(0, 4). Line mm is perpendicular to line kk and intersects line kk at its yy-intercept. What is the xx-intercept of line mm?

Cevabı ve açıklamayı göster

Cevap: 83\frac{8}{3}

Cevap

The xx-intercept of line mm is 83\frac{8}{3}.
Line kk has a slope of 400(6)=23\frac{4 - 0}{0 - (-6)} = \frac{2}{3}. Because line mm is perpendicular to line kk, its slope is the negative reciprocal, 32-\frac{3}{2}. Line mm intersects line kk at its yy-intercept (0,4)(0, 4), giving line mm the equation y=32x+4y = -\frac{3}{2}x + 4. Setting y=0y = 0 yields 0=32x+40 = -\frac{3}{2}x + 4, which solves to x=83x = \frac{8}{3}.

Adım Adım Çözüm

1
Calculate the slope of line kk.
The slope mk=400(6)=46=23m_k = \frac{4 - 0}{0 - (-6)} = \frac{4}{6} = \frac{2}{3}.
The slope of a line passing through (x1,y1)(x_1, y_1) and (x2,y2)(x_2, y_2) is calculated using y2y1x2x1\frac{y_2 - y_1}{x_2 - x_1}.
2
Determine the slope and yy-intercept of line mm.
The slope of line mm is mm=32m_m = -\frac{3}{2}, and its yy-intercept is (0,4)(0, 4).
Perpendicular lines have slopes that are negative reciprocals of each other, and line mm intersects line kk at (0,4)(0, 4).
3
Write the equation of line mm and solve for its xx-intercept.
Setting y=0y = 0 in y=32x+4y = -\frac{3}{2}x + 4 yields 0=32x+4    32x=4    x=830 = -\frac{3}{2}x + 4 \implies \frac{3}{2}x = 4 \implies x = \frac{8}{3}.
The xx-intercept of a line is the value of xx when y=0y = 0.

Anahtar Kavram

Perpendicular line slopes and intercept calculations
Soru 1939Soru

Passage:
In 1856, American scientist Eunice Newton Foote presented a paper demonstrating the heat-trapping capabilities of atmospheric gases. Using glass cylinders exposed to sunlight, Foote measured the temperature changes in containers filled with compressed air, hydrogen, oxygen, and carbon dioxide. Her measurements revealed that the cylinder containing moist carbon dioxide experienced the highest temperature increase and took the longest duration to cool down after being removed from sunlight. Based on these observations, Foote explicitly posited that an atmosphere enriched with carbon dioxide would impart a significantly higher temperature to Earth. Although John Tyndall is frequently credited with discovering the atmospheric greenhouse effect through his later 1859 experiments using infrared spectrophotometry, Foote’s earlier empirical work established the direct relationship between carbon dioxide concentrations and solar radiative heating, despite her apparatus omitting isolated infrared radiation sources.

Which of the following statements about Eunice Newton Foote's 1856 experiment are explicitly supported by the passage? Select all that apply.

Geçerli olan tümünü seçin

Cevabı ve açıklamayı göster

Cevap: Foote recorded temperature changes in glass cylinders containing several different gases, including hydrogen and carbon dioxide.; The container filled with moist carbon dioxide required a longer period to cool down than containers holding the other tested gases.

Cevap

The statements confirming that Foote recorded temperatures across multiple gases (including hydrogen and carbon dioxide) and that the moist carbon dioxide container required the longest time to cool down are both explicitly supported by the passage.
The passage directly supports two statements: it lists hydrogen and carbon dioxide among the gases tested in Foote's glass cylinders, and it explicitly states that the container holding moist carbon dioxide took the longest duration to cool down compared to the other tested containers.

Adım Adım Çözüm

1
Locate the sentence detailing the specific gases placed in the glass cylinders during Foote's experiment.
The text explicitly names compressed air, hydrogen, oxygen, and carbon dioxide.
Verifies whether testing hydrogen and carbon dioxide is directly stated.
2
Examine the passage for statements regarding the cooling duration of the moist carbon dioxide container.
The text explicitly states that the cylinder containing moist carbon dioxide 'took the longest duration to cool down after being removed from sunlight.'
Verifies whether the relative cooling time claim is explicitly supported.
3
Evaluate the statement attributing infrared spectrophotometry to Foote's methodology.
The passage states that infrared spectrophotometry was introduced by John Tyndall in 1859 and explicitly mentions that Foote's apparatus omitted isolated infrared radiation sources.
Eliminates statements that misread or misattribute passage details.

Anahtar Kavram

Explicit Detail Retrieval
Soru 1940Soru

A venture capital fund allocated an initial sum of money between Portfolio Alpha and Portfolio Beta, with Portfolio Alpha receiving 60%60\% of the total sum and Portfolio Beta receiving the remaining 40%40\%. During the first year, the value of Portfolio Alpha increased by 20%20\%, while the value of Portfolio Beta decreased by 15%15\%. During the second year, the value of Portfolio Alpha decreased by 10%10\% relative to its value at the end of the first year, while the value of Portfolio Beta increased by 25%25\% relative to its value at the end of the first year. By what percent did the total combined value of the two portfolios increase from the initial allocation to the end of the second year?

Cevabı ve açıklamayı göster

Cevap: 7.3

Cevap

The total combined value of the two portfolios increased by 7.3%.
To find the net percent change over the two-year period, track each portfolio's value year by year. Assuming an initial combined total of 100,PortfolioAlphabeginsat100, Portfolio Alpha begins at 60 and Portfolio Beta at 40.BytheendofYear1,Alphaincreasesby2040. By the end of Year 1, Alpha increases by 20% to 72 (60×1.2060 \times 1.20), while Beta decreases by 15% to 34(34 ( 40 \times 0.85 ).InYear2,Alphadecreasesby10). In Year 2, Alpha decreases by 10% relative to its Year 1 ending value, becoming 64.80 (72×0.9072 \times 0.90), while Beta increases by 25% relative to its Year 1 ending value, becoming 42.50(42.50 ( 34 \times 1.25 ).ThetotalcombinedvalueattheendofYear2is). The total combined value at the end of Year 2 is 64.80 + 42.50=42.50 = 107.30. Relative to the initial $100 allocation, this represents a net increase of 7.3%.

Adım Adım Çözüm

1
Assign a convenient base value for the initial total investment.
Assume an initial total allocation of 100.PortfolioAlphastartswith100. Portfolio Alpha starts with 60 and Portfolio Beta starts with $40.
Percent changes are proportional and scale-invariant, making $100 a simple base value for calculation.
2
Compute the value of each portfolio at the end of Year 1.
Portfolio Alpha = 60×(1+0.20)=60 \times (1 + 0.20) = 72. Portfolio Beta = 40×(10.15)=40 \times (1 - 0.15) = 34.
Apply Year 1 growth (+20%) and loss (-15%) to their respective starting funds.
3
Compute the value of each portfolio at the end of Year 2.
Portfolio Alpha = 72×(10.10)=72 \times (1 - 0.10) = 64.80. Portfolio Beta = 34×(1+0.25)=34 \times (1 + 0.25) = 42.50.
Apply Year 2 changes (-10% and +25%) to the Year 1 ending values rather than the original principal.
4
Find the final total combined value and calculate the overall net percentage increase.
Combined Year 2 value = 64.80+64.80 + 42.50 = $107.30. Net percentage increase = \frac{107.30 - 100}{100} \times 100\% = 7.3\%.
Compare the final combined sum of 107.30totheinitialcombinedsumof107.30 to the initial combined sum of 100.

Anahtar Kavram

Successive percent changes with shifting base values across multiple assets
ÖncekiSayfa 97 / 107Sonraki
Tüm alıştırma soruları — GRE General Test | Examkin