Tüm alıştırma soruları

2131 soru

Soru 1841Soru

Match each advanced vocabulary word on the left with its most precise functional near-synonym on the right.

Soldaki öğeye tıklayın, sonra eşleşen sağdaki öğeye tıklayın

Öğeler

obdurate
laconic
abstruse
effervescent

Eşleşmeler

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Cevap

The correct pairings are: obdurate matches obstinate; laconic matches taciturn; abstruse matches recondite; effervescent matches ebullient.
Each left-hand term is paired with its precise semantic equivalent: obdurate means obstinate (stubborn); laconic means taciturn (succinct/uncommunicative); abstruse means recondite (esoteric/obscure); and effervescent means ebullient (exuberant).

Adım Adım Çözüm

1
Analyze the meaning of 'obdurate'.
Defines an unyielding or stubborn disposition.
Find a right-hand term with equivalent meaning, which is 'obstinate'.
2
Analyze the meaning of 'laconic'.
Refers to using concise or minimal phrasing in speech.
Match with 'taciturn', which describes being untalkative or concise.
3
Analyze the meaning of 'abstruse'.
Describes ideas that are complex, deep, or hard to comprehend.
Match with 'recondite', which means obscure or little-known.
4
Analyze the meaning of 'effervescent'.
Refers figuratively to vivacious, enthusiastic demeanor.
Match with 'ebullient', which means overflowing with enthusiasm.

Anahtar Kavram

Identifying direct semantic equivalence and primary definitions of high-frequency GRE vocabulary.
Soru 1842Soru

Read the passage below:

While early musicologists dismissed the composer��s late symphonic sketches as mere (i)________ fragments never intended for performance, recent archival discoveries reveal that these draft scores were in fact (ii)________ to her final masterpiece, as key thematic motifs from the sketches recur directly throughout the completed work.

Which of the following combinations of words logically completes the blanks in the passage?

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Cevap: (i) chimerical, (ii) integral

Cevap

The combination '(i) chimerical, (ii) integral' logically completes both blanks by establishing the required contrast between the initial dismissal of the sketches and their actual importance to the final work.
The correct choice establishing '(i) chimerical' and '(ii) integral' satisfies both local context clues and structural contrast. 'Chimerical' fits the view of the sketches as unrealizable fragments, while 'integral' aligns with the evidence that their core motifs appear throughout the final masterpiece.

Adım Adım Çözüm

1
Analyze structural signals and contrast pivots in the sentence.
The opening word 'While' and the phrase 'in fact' indicate a contrast between how early musicologists viewed the sketches ('dismissed... as mere (i)________') and what recent discoveries demonstrate ('were in fact (ii)________').
Tracking inter-blank relationships requires identifying the logical pivot connecting the two clauses.
2
Determine the required meaning for Blank (i).
Because the sketches were 'dismissed' and described as 'never intended for performance', Blank (i) requires a word meaning fanciful, unrealistic, or imaginary, such as 'chimerical'.
The context clue 'mere... fragments never intended for performance' defines the negative characterization in the first clause.
3
Determine the required meaning for Blank (ii) using cross-sentence evidence.
The concluding clause notes that 'key thematic motifs from the sketches recur directly throughout the completed work,' indicating that the draft scores were essential or central, making 'integral' the correct fit.
The final clause provides the evidence confirming the exact degree of importance needed for the second blank.

Anahtar Kavram

Multi-Blank Dependency Tracking
Soru 1843Soru

A positive integer nn yields a remainder of 77 when divided by 1212. What is the remainder when the expression 5n+35n + 3 is divided by 66?

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Cevap: 22

Cevap

The remainder when 5n+35n + 3 is divided by 66 is 22.
Since nn leaves a remainder of 77 when divided by 1212, we can write n=12k+7n = 12k + 7 for some integer k0k \ge 0. Substituting this into 5n+35n + 3 yields 5(12k+7)+3=60k+385(12k + 7) + 3 = 60k + 38. Factoring out 66 gives 6(10k+6)+26(10k + 6) + 2. Because 6(10k+6)6(10k + 6) is divisible by 66, the remainder of the expression when divided by 66 is 22.

Adım Adım Çözüm

1
Express nn in terms of the division algorithm for divisor 1212.
n=12k+7n = 12k + 7 for some non-negative integer kk
An integer that leaves a remainder of 77 when divided by 1212 can be represented as 12k+712k + 7.
2
Substitute the expression for nn into 5n+35n + 3 and simplify.
5(12k+7)+3=60k+35+3=60k+385(12k + 7) + 3 = 60k + 35 + 3 = 60k + 38
Algebraic expansion allows us to analyze the entire expression modulo 66.
3
Determine the remainder of 60k+3860k + 38 when divided by 66.
60k+38=6(10k+6)+260k + 38 = 6(10k + 6) + 2
Since 60k+3660k + 36 is an exact multiple of 66, the leftover term 22 is the remainder.

Anahtar Kavram

Properties of Integers and Remainder Arithmetic
Tahmini Süre:1m 30s
Soru 1844Soru

Let mm and nn be positive integers such that mm is divisible by 1818 and nn is divisible by 1515. Which of the following integers MUST be a divisor of the product mnm \cdot n? Select all such values.

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Cevap: 5454; 9090; 135135

Cevap

The integers 5454, 9090, and 135135 must be divisors of the product mnm \cdot n.
Since mm is a multiple of 1818 (21×322^1 \times 3^2) and nn is a multiple of 1515 (31×513^1 \times 5^1), their product mnm \cdot n must be a multiple of 18×15=27018 \times 15 = 270. The prime factorization of 270270 is 21×33×512^1 \times 3^3 \times 5^1. Any integer that divides 270270 is guaranteed to divide mnm \cdot n for all valid values of mm and nn. The numbers 5454 (21×332^1 \times 3^3), 9090 (21×32×512^1 \times 3^2 \times 5^1), and 135135 (33×513^3 \times 5^1) are all divisors of 270270.

Adım Adım Çözüm

1
Express mm and nn in terms of their minimal prime factorizations.
m=18a=21×32×am = 18a = 2^1 \times 3^2 \times a and n=15b=31×51×bn = 15b = 3^1 \times 5^1 \times b for positive integers aa and bb.
Divisibility conditions specify the minimum prime factors that mm and nn must contain.
2
Find the minimal guaranteed prime factorization of the product mnm \cdot n.
mn=(21×32×a)×(31×51×b)=21×33×51×(ab)=270×abm \cdot n = (2^1 \times 3^2 \times a) \times (3^1 \times 5^1 \times b) = 2^1 \times 3^3 \times 5^1 \times (ab) = 270 \times ab.
Multiplying mm and nn combines their guaranteed prime factor powers.
3
Determine which choices divide 270=21×33×51270 = 2^1 \times 3^3 \times 5^1 without requiring additional factors of aa or bb.
54=21×3354 = 2^1 \times 3^3, 90=21×32×5190 = 2^1 \times 3^2 \times 5^1, and 135=33×51135 = 3^3 \times 5^1 all divide 270270. Numbers requiring 222^2 (3636 and 6060) do not necessarily divide 270270.
A number MUST divide mnm \cdot n if its prime factor powers do not exceed the minimum guaranteed powers in mnm \cdot n.

Anahtar Kavram

Divisibility of Integer Products via Prime Factorization
Soru 1845Soru

A sequence a1,a2,a3,,ana_1, a_2, a_3, \dots, a_n is defined by a1=1a_1 = 1 and an=2an1+3a_n = 2a_{n-1} + 3 for all integers n2n \geq 2. What is the value of a4a_4?

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Cevap: 2929

Cevap

The value of a4a_4 is 2929.
Using the recursive rule an=2an1+3a_n = 2a_{n-1} + 3 starting with a1=1a_1 = 1, we compute a2=2(1)+3=5a_2 = 2(1) + 3 = 5, a3=2(5)+3=13a_3 = 2(5) + 3 = 13, and finally a4=2(13)+3=29a_4 = 2(13) + 3 = 29.

Adım Adım Çözüm

1
Calculate the second term a2a_2 using the recursive formula with a1=1a_1 = 1.
a2=2(1)+3=5a_2 = 2(1) + 3 = 5
The recursive rule requires the previous term to compute the next term.
2
Calculate the third term a3a_3 using a2=5a_2 = 5.
a3=2(5)+3=13a_3 = 2(5) + 3 = 13
Apply the recursive definition an=2an1+3a_n = 2a_{n-1} + 3 for n=3n = 3.
3
Calculate the fourth term a4a_4 using a3=13a_3 = 13.
a4=2(13)+3=29a_4 = 2(13) + 3 = 29
Apply the recursive definition an=2an1+3a_n = 2a_{n-1} + 3 for n=4n = 4.

Anahtar Kavram

Recursive Sequences
Soru 1846Soru

In his investigation of neural network architecture, the neuroscientist argued that advanced cognitive mechanisms do not eradicate primitive reflexes, but rather function to arrest their autonomous execution, thereby allowing higher-order executive control to intervene.

In the context of the sentence, the word "arrest" most nearly means which of the following?

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Cevap: inhibit

Cevap

In this passage, 'arrest' is used in its secondary definition meaning to inhibit, check, or bring to a halt, referring to stopping the autonomous execution of primitive reflexes.
In the context of neural function, 'arrest' means to check, halt, or slow down progress. Using 'inhibit' accurately conveys that advanced cognitive mechanisms hold back automatic responses to allow deliberate decision-making.

Adım Adım Çözüm

1
Analyze the sentence context and structural clues.
The sentence states that cognitive mechanisms do not 'eradicate' primitive reflexes, but function to affect their 'autonomous execution' so that executive control can intervene.
Understanding the contrast with 'eradicate' and the goal of enabling intervention reveals that reflexes must be paused or suppressed rather than destroyed or legally detained.
2
Evaluate the primary versus secondary meanings of 'arrest'.
'Arrest' primarily refers to legal apprehension or imprisonment, but secondarily means to check, halt, or inhibit a biological or mechanical process.
A biological process like reflex execution cannot be legally detained, so the secondary definition meaning 'to inhibit or stop' must be applied.
3
Select the option that matches the secondary meaning in context.
'Inhibit' accurately matches the meaning of stopping or checking autonomous reflex execution.
Inhibition directly describes preventing an automated response from proceeding.

Anahtar Kavram

Secondary Meaning of Polysemous Words in Context
Soru 1847Soru

Let A=0.000032×10nA = 0.000032 \times 10^{n} and B=8.0×10n3B = 8.0 \times 10^{n-3}, where nn is an integer. If A2B=1.28×104\frac{A^2}{B} = 1.28 \times 10^{-4}, what is the value of nn?

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Cevap: 33

Cevap

The value of nn is 33.
Rewriting 0.0000320.000032 as 3.2×1053.2 \times 10^{-5} allows AA to be expressed as 3.2×10n53.2 \times 10^{n-5}. Squaring AA yields 10.24×102n1010.24 \times 10^{2n-10}. Dividing by B=8.0×10n3B = 8.0 \times 10^{n-3} gives 1.28×10n71.28 \times 10^{n-7}. Equating n7=4n - 7 = -4 directly leads to n=3n = 3.

Adım Adım Çözüm

1
Convert AA to standard scientific notation in terms of nn
A=3.2×105×10n=3.2×10n5A = 3.2 \times 10^{-5} \times 10^n = 3.2 \times 10^{n-5}
The decimal 0.0000320.000032 equals 3.2×1053.2 \times 10^{-5} because the decimal point is shifted 55 places to the right.
2
Calculate A2A^2
A2=(3.2×10n5)2=(3.2)2×102(n5)=10.24×102n10A^2 = (3.2 \times 10^{n-5})^2 = (3.2)^2 \times 10^{2(n-5)} = 10.24 \times 10^{2n-10}
Apply the power of a product rule (ab)k=akbk(ab)^k = a^k b^k and exponent power rule (10p)q=10pq(10^p)^q = 10^{pq}.
3
Divide A2A^2 by BB
\frac{A^2}{B} = \frac{10.24 \times 10^{2n-10}}{8.0 \times 10^{n-3}} = \left(\frac{10.24}{8.0}\right) \times 10^{(2n-10) - (n-3)} = 1.28 \times 10^{n-7}
Divide coefficients (10.24/8.0=1.28)(10.24 / 8.0 = 1.28) and subtract powers of ten exponents ((2n10)(n3)=n7)((2n - 10) - (n - 3) = n - 7).
4
Equate the simplified expression to the given value and solve for nn
1.28×10n7=1.28×104    n7=4    n=31.28 \times 10^{n-7} = 1.28 \times 10^{-4} \implies n - 7 = -4 \implies n = 3
Since the coefficients match (1.281.28), equate the exponents of 1010 to solve for nn.

Anahtar Kavram

Scientific Notation Operations and Exponent Laws
Tahmini Süre:2m 0s
Soru 1848Soru

An investor divided a total capital of $20,000\$20,000 between two accounts. Account A pays a simple annual interest rate of 6%6\%, and Account B pays a simple annual interest rate of 9%9\%. If the total interest earned from both accounts at the end of one year was $1,470\$1,470, how much money was invested in Account A?

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Cevap: $11,000\$11,000

Cevap

The amount invested in Account A was $11,000\$11,000.
Let xx represent the amount invested in Account A. The remaining capital, 20,000x20,000 - x, is invested in Account B. The total interest earned in one year is given by 0.06x+0.09(20,000x)=1,4700.06x + 0.09(20,000 - x) = 1,470. Expanding gives 0.06x+1,8000.09x=1,4700.06x + 1,800 - 0.09x = 1,470, which simplifies to 0.03x=330-0.03x = -330. Dividing by 0.03-0.03 yields x=11,000x = 11,000. Thus, $11,000\$11,000 was invested in Account A.

Adım Adım Çözüm

1
Define the variable for the unknown quantity.
Let xx be the amount in dollars invested in Account A. Then (20,000x)(20,000 - x) is the amount invested in Account B.
Expressing both quantities in terms of a single variable allows setting up a single linear equation.
2
Formulate the total interest equation.
0.06x+0.09(20,000x)=1,4700.06x + 0.09(20,000 - x) = 1,470
Total interest is the sum of interest from Account A (6%6\% of xx) and Account B (9%9\% of 20,000x20,000 - x).
3
Expand and simplify the algebraic equation.
0.06x+1,8000.09x=1,470    0.03x+1,800=1,4700.06x + 1,800 - 0.09x = 1,470 \implies -0.03x + 1,800 = 1,470
Distribute 0.090.09 across (20,000x)(20,000 - x) and combine like terms.
4
Isolate the variable xx.
0.03x=1,4701,800    0.03x=330    x=11,000-0.03x = 1,470 - 1,800 \implies -0.03x = -330 \implies x = 11,000
Subtract 1,8001,800 from both sides and divide by 0.03-0.03 to find xx.

Anahtar Kavram

Linear Equations in One Variable
Tahmini Süre:1m 30s
Soru 1849Soru

Complete the sentence by filling in the blank with the single word that best fits the passage based on its secondary academic meaning.

Aşağıdaki boşlukları doldurun

In her monograph on theoretical metaphysics, the philosopher sought to the deep structural origins of human cognition, moving past superficial explanations to examine its underlying mechanisms.
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Cevap

The word 'plumb' correctly completes the passage, used in its secondary verb sense meaning to measure depth or investigate thoroughly.
The correct word 'plumb' functions as a verb meaning to measure depth or to sound out and examine thoroughly. The passage explicitly contrasts 'superficial explanations' with analyzing 'deep structural origins,' making 'plumb' the most contextually accurate fit.

Adım Adım Çözüm

1
Analyze the surrounding context and contrast clues in the sentence.
The phrase 'moving past superficial explanations to examine its underlying mechanisms' indicates a need for a word that signifies deep, rigorous investigation.
Understanding the contextual contrast between 'superficial' and 'underlying mechanisms' determines the required semantic tone.
2
Identify the standard vocabulary word acting in its secondary usage.
While 'plumb' is most frequently encountered as a noun or adjective relating to verticality or pipework, its secondary verb definition means to measure the depth of water or to examine something deeply and thoroughly.
Using 'plumb' as a verb fits the philosophical context of delving beneath surface-level explanations.

Anahtar Kavram

Secondary and High-Frequency Alternative Meanings
Soru 1850Soru

At the beginning of 2024, a university endowment fund was reallocated across various asset classes. Over the course of 2024, the total value of the endowment fund increased by 30%30\%. In 2025, market downturns caused the total value of the fund to decrease by 20%20\% relative to its value at the end of 2024. If the total value of the endowment fund at the end of 2025 was $520,000\$520,000, what was the total value of the fund at the beginning of 2024?

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Cevap: $500,000\$500,000

Cevap

$500,000\$500,000
The option stating $500,000\$500,000 is correct because a 30%30\% increase followed by a 20%20\% decrease corresponds to multiplying the initial value VV by 1.30×0.80=1.041.30 \times 0.80 = 1.04. Solving 1.04V=520,0001.04V = 520,000 yields V=500,000V = 500,000.

Adım Adım Çözüm

1
Define the initial value variable and express successive percent changes as growth/decay multipliers.
Let VV be the initial value at the start of 2024. A 30%30\% increase corresponds to a multiplier of 1+0.30=1.301 + 0.30 = 1.30. A 20%20\% decrease corresponds to a multiplier of 10.20=0.801 - 0.20 = 0.80.
Successive percentage changes compound multiplicatively on the original base value.
2
Formulate the net equation for the final value.
V×1.30×0.80=520,000    V×1.04=520,000V \times 1.30 \times 0.80 = 520,000 \implies V \times 1.04 = 520,000
Multiplying 1.301.30 by 0.800.80 yields a net factor of 1.041.04, representing a net 4%4\% increase over the two-year period.
3
Solve for the initial value VV.
V=520,0001.04=500,000V = \frac{520,000}{1.04} = 500,000
Dividing the final amount by the combined multiplier isolates the original starting value.

Anahtar Kavram

Successive Percent Changes and Base Value Calculation
Tahmini Süre:1m 30s
Soru 1851Soru

The computational linguist observed that incorporating syntactic tree constraints into the neural model did not merely improve translation accuracy; furthermore, by explicitly modeling grammatical structure, the architecture ________ a significant reduction in semantic errors.

Which two of the following options, when inserted into the blank, fit the meaning of the sentence as a whole and yield completed sentences that are logically equivalent?

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Cevap: yielded; generated

Cevap

The two correct choices are 'yielded' and 'generated', as both words indicate that the architectural enhancement directly produced or brought about the reduction in semantic errors.
The sentence uses the additive/continuation signal 'furthermore' following 'did not merely improve', indicating that the second clause reinforces and builds upon the positive outcome of the first. The words 'yielded' and 'generated' both mean produced or brought about, completing the causal chain logically and producing equivalent sentence meanings.

Adım Adım Çözüm

1
Analyze sentence structure and structural transition signals.
The semi-colon followed by 'furthermore' and the clause 'did not merely... by explicitly modeling...' signals a positive continuation and causal reinforcement of the primary benefit.
Understanding structural signals determines whether the missing word must carry a positive, negative, or neutral causal meaning.
2
Determine the required contextual meaning and valence of the blank.
The blank requires a verb meaning 'produced', 'brought about', or 'resulted in' a positive reduction in errors.
The model's architectural improvement leads directly to the positive outcome of error reduction.
3
Evaluate option pairs for semantic equivalence and contextual fit.
'Yielded' and 'generated' both accurately express that the architecture produced the reduction. In contrast, 'forestalled'/'precluded' reverse the directional logic, while 'portended'/'presaged' incorrectly introduce speculative forecasting rather than direct causation.
GRE Sentence Equivalence requires choosing two words that create completed sentences with identical meaning.

Anahtar Kavram

Interpreting Continuation and Causal Structural Signals
Soru 1852Soru

Match each formal GRE vocabulary word on the left with its most precise functional near-synonym on the right.

Soldaki öğeye tıklayın, sonra eşleşen sağdaki öğeye tıklayın

Öğeler

Profligate
Equanimous
Sycophantic
Recondite

Eşleşmeler

Cevabı ve açıklamayı göster

Cevap

'Profligate' pairs with 'Extravagant', 'Equanimous' pairs with 'Composed', 'Sycophantic' pairs with 'Obsequious', and 'Recondite' pairs with 'Esoteric'.
Each vocabulary term matches its exact semantic counterpart: 'profligate' denotes reckless wastefulness ('extravagant'); 'equanimous' denotes emotional stability under pressure ('composed'); 'sycophantic' denotes servile flattery ('obsequious'); and 'recondite' denotes specialized or obscure knowledge ('esoteric').

Adım Adım Çözüm

1
Analyze the core definition of 'Profligate'
'Profligate' means recklessly extravagant or wasteful in the use of resources.
Find its semantic counterpart on the right, which is 'Extravagant'.
2
Analyze the core definition of 'Equanimous'
'Equanimous' means calm and composed, especially under stress.
Find its semantic counterpart on the right, which is 'Composed'.
3
Analyze the core definition of 'Sycophantic'
'Sycophantic' means behaving in an obsequious or fawning manner toward influential individuals.
Find its semantic counterpart on the right, which is 'Obsequious'.
4
Analyze the core definition of 'Recondite'
'Recondite' means dealing with profound, obscure, or little-known subject matter.
Find its semantic counterpart on the right, which is 'Esoteric'.

Anahtar Kavram

Identifying Synonym and Near-Synonym Pairs
Soru 1853Soru

Complete the passage by filling in each blank with the word that best maintains the logical structure and contextual meaning of the text.

Aşağıdaki boşlukları doldurun

While early architectural historians dismissed the fortress's irregular outer walls as a structural design resulting from hastily improvised repairs, modern spatial analysis reveals that these asymmetric ramparts were systematically to the surrounding terrain to maximize defensive sightlines.
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Cevap

Blank 1: haphazard; Blank 2: calibrated
The concession word 'While' establishes a opposition between early assumptions and modern findings. The descriptive clue 'hastily improvised repairs' dictates that Blank 1 must convey a lack of deliberate planning, which is precisely captured by 'haphazard'. Contrastingly, modern analysis demonstrates that the walls were not random, but 'systematically' fitted to the environment; hence 'calibrated' correctly completes Blank 2 to align with maximizing defensive sightlines.

Adım Adım Çözüm

1
Identify structural transition signals and contrast clues.
The opening concession signal 'While' indicates a contrast between early historians' views and modern spatial analysis findings.
The sentence structure pits past misinterpretations against modern empirical insights.
2
Determine the contextual requirement for Blank 1 based on local clues.
The phrase 'hastily improvised repairs' suggests that early historians viewed the wall design as unplanned, random, or arbitrary; thus 'haphazard' fits Blank 1.
The word in Blank 1 must reflect the lack of order implied by hastily improvised work.
3
Determine the dependency between Blank 1 and Blank 2.
Modern analysis contradicts the initial belief by showing deliberate design. The adverb 'systematically' requires Blank 2 to express careful adjustment to the landscape, making 'calibrated' (or 'adapted') correct.
If the design was systematically executed to maximize sightlines, the ramparts were precisely fitted or calibrated to the topography.

Anahtar Kavram

Multi-Blank Dependency Tracking
Tahmini Süre:1m 15s
Soru 1854Soru

A coffee merchant creates a 5050-pound custom mixture combining Grade A coffee beans, which cost $8\$8 per pound, and Grade B coffee beans, which cost $14\$14 per pound. If the total cost of the mixture must be at least $460\$460 and at most $520\$520, which of the following could be the weight, in pounds, of Grade A coffee beans used in the mixture? Select all such weights.

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Cevap: 3232; 3535; 4040

Cevap

The weight of Grade A coffee beans can be 32 pounds, 35 pounds, or 40 pounds.
Let xx represent the number of pounds of Grade A coffee beans. The remaining 50x50 - x pounds consist of Grade B beans. The total cost of the mixture is given by 8x+14(50x)=7006x8x + 14(50 - x) = 700 - 6x. Setting up the given inequality constraints, we have 4607006x520460 \le 700 - 6x \le 520. Subtracting 700 yields 2406x180-240 \le -6x \le -180. Dividing by 6-6 and reversing the inequality signs gives 30x4030 \le x \le 40. Therefore, any weight of Grade A beans between 30 and 40 pounds inclusive is valid. The values 32, 35, and 40 satisfy this condition.

Adım Adım Çözüm

1
Define variables for the quantities of Grade A and Grade B beans.
Let xx be the weight in pounds of Grade A beans. Then 50x50 - x is the weight in pounds of Grade B beans.
The total weight of the mixture is fixed at 50 pounds.
2
Set up an expression for the total cost of the mixture in terms of xx.
Total Cost = 8x+14(50x)=7006x8x + 14(50 - x) = 700 - 6x.
Multiply the weight of each component by its price per pound.
3
Set up the compound inequality representing the given cost constraints.
4607006x520460 \le 700 - 6x \le 520.
The total cost must be at least $460\$460 and at most $520\$520.
4
Solve the compound inequality for xx.
Subtracting 700 from all parts gives 2406x180-240 \le -6x \le -180. Dividing by 6-6 and reversing the inequality signs yields 30x4030 \le x \le 40.
Dividing by a negative number reverses the direction of the inequality signs.
5
Identify which options fall within the valid range [30,40][30, 40].
The values 32, 35, and 40 fall within the range 30x4030 \le x \le 40.
Any weight between 30 and 40 pounds inclusive satisfies the cost constraint.

Anahtar Kavram

Linear Modeling and Inequality Constraints in Mixture Problems
Tahmini Süre:1m 40s
Soru 1855Soru

An investment fund allocated its total initial capital equally into two separate accounts, Account X and Account Y. Account X earns simple annual interest at a rate of r%r\%, while Account Y earns compound annual interest at the same rate of r%r\%, compounded annually. At the end of 2 years, the total interest earned by Account Y exceeded the total interest earned by Account X by an amount equal to 4%4\% of the initial amount placed in Account X. What was the net percentage increase in the fund's total combined capital over the 2-year period?

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Cevap: 42%

Cevap

42%
The correct answer of 42% is found by recognizing that the 2-year difference between compound interest and simple interest at rate r%r\% equals P(r/100)2P(r/100)^2. Setting this difference to 0.04P0.04P yields r=20%r = 20\%. At r=20%r = 20\%, Account X produces 0.40P0.40P in simple interest, while Account Y produces 0.44P0.44P in compound interest. Together, they generate 0.84P0.84P in interest on a total initial investment of 2P2P, resulting in a net fund increase of (0.84P/2P)×100%=42%(0.84P / 2P) \times 100\% = 42\%.

Adım Adım Çözüm

1
Set up expressions for interest earned by each account after 2 years
Let PP be the initial capital in Account X (so Account Y also starts with PP, making total initial capital 2P2P). Simple interest for Account X is IX=P2r100=0.02rPI_X = P \cdot \frac{2r}{100} = 0.02r P. Compound interest for Account Y is IY=P[(1+r100)21]=P(2r100+r210000)I_Y = P\left[\left(1 + \frac{r}{100}\right)^2 - 1\right] = P\left(\frac{2r}{100} + \frac{r^2}{10000}\right).
Establishes the interest expressions based on simple vs. compound interest formulas over a 2-year period.
2
Calculate the annual interest rate rr
Difference in interest: IYIX=P(r210000)I_Y - I_X = P\left(\frac{r^2}{10000}\right). Given this equals 4%4\% of PP (0.04P0.04P), we have r210000=0.04    r2=400    r=20%\frac{r^2}{10000} = 0.04 \implies r^2 = 400 \implies r = 20\%.
Isolates the interest rate rr using the difference between compound and simple interest.
3
Determine total interest earned across both accounts
For Account X: IX=0.02(20)P=0.40PI_X = 0.02(20)P = 0.40P. For Account Y: IY=0.40P+0.04P=0.44PI_Y = 0.40P + 0.04P = 0.44P. Total interest earned = 0.40P+0.44P=0.84P0.40P + 0.44P = 0.84P.
Sums the returns of both portfolio components.
4
Compute the net percentage increase of the total fund
Total initial capital = 2P2P. Net percentage increase = Total InterestTotal Initial Capital×100%=0.84P2P×100%=42%\frac{\text{Total Interest}}{\text{Total Initial Capital}} \times 100\% = \frac{0.84P}{2P} \times 100\% = 42\%.
Calculates the overall percent change using the correct part-to-whole base (total initial investment 2P2P).

Anahtar Kavram

Simple vs. Compound Interest Base Shift and Net Percent Change
Soru 1856Soru

Let xx, yy, and zz be non-zero integers that satisfy the following three conditions:

I. (1)xy+z=1(-1)^{x y + z} = -1
II. (1)xz+y=1(-1)^{x z + y} = 1
III. x3yz2<0x^3 y z^2 < 0

Which of the following statements MUST be true?

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Cevap: xx and yy are both even integers, and xy<0x y < 0

Cevap

xx and yy are both even integers, and xy<0x y < 0
From Condition I, (1)xy+z=1(-1)^{xy+z} = -1 implies xy+zxy + z is odd, so xyxy and zz have opposite parity. From Condition II, (1)xz+y=1(-1)^{xz+y} = 1 implies xz+yxz + y is even, so xzxz and yy have the same parity. If xx were odd, xyxy would share the parity of yy, and xzxz would share the parity of zz. This would mean yy and zz must have opposite parity (from Condition I) and the same parity (from Condition II), which is impossible. Thus, xx must be even. With xx even, xyxy is even, so zz must be odd for xy+zxy + z to be odd. Likewise, xzxz is even, so yy must be even for xz+yxz + y to be even. Finally, from Condition III, since z2>0z^2 > 0 for non-zero zz, x3yz2<0x^3 y z^2 < 0 reduces to x3y<0x^3 y < 0, which means xy<0xy < 0. Thus, xx and yy are both even integers, and xy<0xy < 0.

Adım Adım Çözüm

1
Analyze Condition I for parity requirements
xy+zx y + z must be an odd integer
Since (1)k=1(-1)^k = -1 if and only if kk is an odd integer, xy+zx y + z is odd. Thus, xyx y and zz must have opposite parity.
2
Analyze Condition II for parity requirements
xz+yx z + y must be an even integer
Since (1)k=1(-1)^k = 1 if and only if kk is an even integer, xz+yx z + y is even. Thus, xzx z and yy must have the same parity.
3
Determine the parity of xx, yy, and zz using proof by contradiction
xx is even, yy is even, and zz is odd
If xx were odd, then xyx y would have the same parity as yy, and xzx z would have the same parity as zz. Condition I would require yy and zz to have opposite parity, while Condition II would require yy and zz to have the same parity, a contradiction. Therefore, xx must be even. Since xx is even, xyx y is even, making zz odd (from Condition I). Similarly, xzx z is even, making yy even (from Condition II).
4
Analyze Condition III for sign requirements
xy<0x y < 0
Since zz is a non-zero integer, z2>0z^2 > 0. The inequality x3yz2<0x^3 y z^2 < 0 simplifies to x3y<0x^3 y < 0. Since x3x^3 has the same sign as xx, x3y<0x^3 y < 0 implies xy<0x y < 0.

Anahtar Kavram

Parity rules for exponentiation and basic arithmetic operations, combined with sign rules for products
Soru 1857Soru

A positive integer nn has the prime factorization 2a3b5c2^a \cdot 3^b \cdot 5^c, where aa, bb, and cc are positive integers. Given that gcd(n,7200)=360\gcd(n, 7{}200) = 360 and lcm(n,1080)=3240\text{lcm}(n, 1{}080) = 3{}240, what is the value of a+b+ca + b + c?

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Cevap: 8

Cevap

8
By prime factorizing each given term, 7200=2532527{}200 = 2^5 \cdot 3^2 \cdot 5^2, 360=233251360 = 2^3 \cdot 3^2 \cdot 5^1, 1080=2333511{}080 = 2^3 \cdot 3^3 \cdot 5^1, and 3240=2334513{}240 = 2^3 \cdot 3^4 \cdot 5^1. Applying the definition of GCD as taking the minimum exponent gives min(a,5)=3    a=3\min(a, 5) = 3 \implies a = 3 and min(c,2)=1    c=1\min(c, 2) = 1 \implies c = 1. Applying the definition of LCM as taking the maximum exponent gives max(b,3)=4    b=4\max(b, 3) = 4 \implies b = 4. Thus, a+b+c=3+4+1=8a + b + c = 3 + 4 + 1 = 8.

Adım Adım Çözüm

1
Find the prime factorizations of the given integers and the GCD/LCM values.
7200=2532527{}200 = 2^5 \cdot 3^2 \cdot 5^2, 360=233251360 = 2^3 \cdot 3^2 \cdot 5^1, 1080=2333511{}080 = 2^3 \cdot 3^3 \cdot 5^1, and 3240=2334513{}240 = 2^3 \cdot 3^4 \cdot 5^1.
Decomposing into prime factors allows direct comparison of exponents using GCD (minimum exponent) and LCM (maximum exponent) rules.
2
Analyze the GCD condition gcd(n,7200)=360\gcd(n, 7{}200) = 360.
min(a,5)=3    a=3\min(a, 5) = 3 \implies a = 3, min(b,2)=2    b2\min(b, 2) = 2 \implies b \ge 2, and min(c,2)=1    c=1\min(c, 2) = 1 \implies c = 1.
The exponent of each prime factor in gcd(x,y)\gcd(x, y) is the minimum of their respective exponents in xx and yy.
3
Analyze the LCM condition lcm(n,1080)=3240\text{lcm}(n, 1{}080) = 3{}240.
max(a,3)=3    a3\max(a, 3) = 3 \implies a \le 3, max(b,3)=4    b=4\max(b, 3) = 4 \implies b = 4, and max(c,1)=1    c1\max(c, 1) = 1 \implies c \le 1.
The exponent of each prime factor in lcm(x,y)\text{lcm}(x, y) is the maximum of their respective exponents in xx and yy.
4
Combine the exponent constraints to determine aa, bb, and cc, then calculate their sum.
a=3a = 3, b=4b = 4, and c=1c = 1, so a+b+c=3+4+1=8a + b + c = 3 + 4 + 1 = 8.
Combining a=3a=3, b2b \ge 2 with b=4b=4, and c=1c=1 with c1c \le 1 uniquely specifies (a,b,c)=(3,4,1)(a,b,c) = (3,4,1).

Anahtar Kavram

Prime Exponent Analysis of Greatest Common Divisor and Least Common Multiple
Tahmini Süre:2m 0s
Soru 1858Soru

A technology firm monitors its active user base and average monthly server cost per user across four consecutive quarters:

- In Quarter 1, the total server cost was CC.
- In Quarter 2, the active user base increased by 25%25\% relative to Quarter 1, while the average monthly server cost per user decreased by 20%20\% relative to Quarter 1.
- In Quarter 3, the active user base decreased by x%x\% relative to Quarter 2, while the average monthly server cost per user increased by x%x\% relative to Quarter 2, where x>0x > 0.
- In Quarter 4, the active user base increased by 20%20\% relative to Quarter 3, while the average monthly server cost per user decreased by 10%10\% relative to Quarter 3.

If the total server cost in Quarter 4 was 3.68%3.68\% greater than the total server cost in Quarter 1, what is the value of xx?

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Cevap: 2020

Cevap

The value of xx is 2020.
The correct response is 20. Total cost in Quarter 1 is C1=N1P1=CC_1 = N_1 P_1 = C. In Quarter 2, C2=(1.25N1)(0.80P1)=1.00CC_2 = (1.25 N_1)(0.80 P_1) = 1.00 C. In Quarter 3, the user base and cost per user change by x%-x\% and +x%+x\%, giving C3=C(1x100)(1+x100)=C(1x210,000)C_3 = C \left(1 - \frac{x}{100}\right)\left(1 + \frac{x}{100}\right) = C \left(1 - \frac{x^2}{10,000}\right). In Quarter 4, the overall factor becomes 1.20×0.90=1.081.20 \times 0.90 = 1.08, so C4=1.08C(1x210,000)C_4 = 1.08 C \left(1 - \frac{x^2}{10,000}\right). Setting 1.08(1x210,000)=1.03681.08 \left(1 - \frac{x^2}{10,000}\right) = 1.0368 yields 1x210,000=0.961 - \frac{x^2}{10,000} = 0.96, from which x210,000=0.04\frac{x^2}{10,000} = 0.04, giving x2=400x^2 = 400 and x=20x = 20.

Adım Adım Çözüm

1
Define total cost variables for Quarter 1 and Quarter 2.
Quarter 1 cost C1=N1P1=CC_1 = N_1 P_1 = C. Quarter 2 user base N2=1.25N1N_2 = 1.25 N_1 and cost per user P2=0.80P1P_2 = 0.80 P_1, so C2=(1.25N1)(0.80P1)=1.00N1P1=CC_2 = (1.25 N_1)(0.80 P_1) = 1.00 N_1 P_1 = C.
Total cost is the product of user count and cost per user; successive changes in Quarter 2 offset each other completely.
2
Calculate total cost in Quarter 3 in terms of xx.
Quarter 3 user base N3=N2(1x100)N_3 = N_2\left(1 - \frac{x}{100}\right) and cost per user P3=P2(1+x100)P_3 = P_2\left(1 + \frac{x}{100}\right). Total cost C3=N3P3=C2(1x100)(1+x100)=C(1x210,000)C_3 = N_3 P_3 = C_2 \left(1 - \frac{x}{100}\right)\left(1 + \frac{x}{100}\right) = C \left(1 - \frac{x^2}{10,000}\right).
Applying the difference of squares identity (1u)(1+u)=1u2(1 - u)(1 + u) = 1 - u^2 for compound percentage change.
3
Calculate total cost in Quarter 4 and set up the equation with Quarter 1 cost.
Quarter 4 user base N4=1.20N3N_4 = 1.20 N_3 and cost per user P4=0.90P3P_4 = 0.90 P_3, giving C4=(1.20)(0.90)C3=1.08C3=1.08C(1x210,000)C_4 = (1.20)(0.90) C_3 = 1.08 C_3 = 1.08 C \left(1 - \frac{x^2}{10,000}\right). Since C4=1.0368CC_4 = 1.0368 C, we get 1.08(1x210,000)=1.03681.08 \left(1 - \frac{x^2}{10,000}\right) = 1.0368.
Quarter 4 expenditure compounds the Quarter 3 cost by a factor of 1.20×0.90=1.081.20 \times 0.90 = 1.08.
4
Solve for xx.
1x210,000=1.03681.08=0.96    x210,000=0.04    x2=400    x=201 - \frac{x^2}{10,000} = \frac{1.0368}{1.08} = 0.96 \implies \frac{x^2}{10,000} = 0.04 \implies x^2 = 400 \implies x = 20.
Dividing 1.03681.0368 by 1.081.08 yields 0.960.96, giving x2=400x^2 = 400 and x=20x = 20 since x>0x > 0.

Anahtar Kavram

Compounding successive percent changes across multiple factors and using algebraic identities for net percent change.
Tahmini Süre:2m 30s
Soru 1859Soru

Far from being a purely ______ shift in demographic distribution, the rapid growth of suburban micro-cities reflects profound underlying changes in workforce mobility and regional economics.

Which two of the following answer choices, when inserted into the sentence, produce completed sentences that are similar in meaning?

Geçerli olan tümünü seçin

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Cevap: superficial; cosmetic

Cevap

The words 'superficial' and 'cosmetic' complete the sentence to produce equivalent meanings.
The sentence relies on the contrast signal 'Far from being a purely ______ shift...' to oppose 'profound underlying changes'. The correct choices must both mean surface-level or minor. The words 'superficial' and 'cosmetic' both carry this meaning and yield completed sentences with equivalent sense.

Adım Adım Çözüm

1
Analyze sentence syntax and structural transition clues
The opening concession 'Far from being a purely ______ shift' establishes a direct contrast with 'profound underlying changes' in the second clause.
The contrast pivot signals that the target word must mean shallow, surface-level, or minor.
2
Evaluate candidate vocabulary for contextual fit and synonymy
'Superficial' and 'cosmetic' both denote surface-level or non-essential characteristics, perfectly contrasting with 'profound'.
Both words complete the sentence with logically coherent and identical meanings.
3
Eliminate invalid distractors and false synonym pairs
'Aesthetic' and 'artistic' form a synonym pair but fail contextually. 'Ephemeral' fits tone but lacks a partner. 'Spatial' is topically relevant but lacks contrast and a pair.
GRE Sentence Equivalence requires both contextual fit and absolute semantic equivalence between the two chosen words.

Anahtar Kavram

Identifying Synonym and Near-Synonym Pairs in Context
Tahmini Süre:1m 0s
Soru 1860Soru

A car travels a total distance of 120120 miles. For the first 6060 miles, the car travels at an average speed of 3030 miles per hour, and for the remaining 6060 miles, the car travels at an average speed of 6060 miles per hour. What is the average speed of the car, in miles per hour, for the entire 120120-mile trip?

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Cevap: 40

Cevap

The average speed of the car for the entire trip is 4040 miles per hour.
The overall average speed is determined by dividing total distance (120120 miles) by total time (33 hours), yielding 4040 miles per hour.

Adım Adım Çözüm

1
Calculate time taken for the first segment
Time = 22 hours
Using Time=DistanceSpeed\text{Time} = \frac{\text{Distance}}{\text{Speed}}, 6030=2\frac{60}{30} = 2 hours.
2
Calculate time taken for the second segment
Time = 11 hour
Using Time=DistanceSpeed\text{Time} = \frac{\text{Distance}}{\text{Speed}}, 6060=1\frac{60}{60} = 1 hour.
3
Determine total distance and total time
Total distance = 120120 miles, Total time = 33 hours
Add distances (60+60=12060 + 60 = 120) and times (2+1=32 + 1 = 3).
4
Calculate overall average speed
Average speed = 4040 miles per hour
Divide total distance by total time: 1203=40\frac{120}{3} = 40.

Anahtar Kavram

Average Speed and Rates
Tahmini Süre:1m 0s
ÖncekiSayfa 93 / 107Sonraki
Tüm alıştırma soruları — GRE General Test | Examkin