GRE 语文与数量推理练习

Ephemeral means lasting for a very short time, so fleeting is the closest match.

Laconic describes speech that uses very few words, so brief is correct.

To undermine means to weaken or damage, often by exposing a flaw.

Candid means truthful and straightforward, so honest is the best match.

Mitigate means to make something less severe or harmful, so it describes reducing the impact of a problem. Example: 'Good planning can mitigate the risks of the project.'

Primary purpose refers to the author's central reason or goal for writing the passage.

An inference is a conclusion drawn logically from evidence in the text.

Ambivalent describes having conflicting or mixed feelings about something, so a person can feel both positive and negative at the same time. Example: 'She felt ambivalent about moving abroad.'

Erudite means having or showing extensive scholarly knowledge, often gained through deep study. Example: 'The erudite professor answered every question in detail.'

Pragmatic means dealing with things sensibly and realistically, focusing on practical results rather than ideals. Example: 'A pragmatic approach solves the problem quickly.'

Frivolous means lacking seriousness or importance, so something frivolous is not worth treating as weighty. Example: 'The committee dismissed the complaint as frivolous.'

Robust means strong and reliable, especially under varied conditions, so a robust system continues working when stressed. Example: 'The network has a robust design that handles heavy traffic.'

Viable means capable of working successfully, so a viable plan can be carried out in practice. Example: 'The proposal is economically viable.'

Arbitrary means based on random choice or personal whim rather than reason.

Consensus is general agreement among a group, reached after considering different views. Example: 'The team reached a consensus on the new schedule.'

Delineate means to describe or portray something precisely, making its boundaries or details clear. Example: 'The report delineates the responsibilities of each department.'

Impartial means treating all rivals or sides equally and without bias.

Plausible means seeming reasonable or probable, so an explanation can be believable even before proof. Example: 'The scientist offered a plausible explanation for the results.'

Obscure can mean not discovered or known, or difficult to understand.

Scrutinize means to examine or inspect closely and carefully, often to find errors or hidden details. Example: 'Auditors scrutinize every expense before approving it.'

Adversarial means involving conflict or opposition, so two sides are working against each other. Example: 'The debate became adversarial rather than cooperative.'

Sparse means thinly scattered or occurring in small amounts, so there is very little of something. Example: 'Vegetation is sparse in the desert.'

Coherent means logical, consistent, and clearly connected, so the parts fit together smoothly. Example: 'Her essay presents a coherent argument.'

Corroborate means to confirm or give support to a statement or theory.

Subtract 7 from both sides of the equation to isolate x: x + 7 = 15 becomes x = 15 - 7 = 8.

Convert 30% to 0.30, then multiply: 30% of 90 is 90 × 0.30 = 27.

Distribute 2 over both terms inside the parentheses: 2(x + 4) = 2x + 8.

In y = mx + b, m is the slope, so the slope is 3.

Area = (1/2) × base × height = (1/2) × 6 × 8 = 24.

The positive square root of 81 is 9 because 9 × 9 = 81; the negative root is -9.

A quadrilateral has 4 sides, so its angles sum to (4 - 2) × 180 = 360 degrees.

The exponent 5 means multiply 2 five times: 2^5 = 2 × 2 × 2 × 2 × 2 = 32.

Convert the fraction to a decimal by dividing: 3/4 = 0.75, and multiplying by 100 gives 75%.

Substitute x = 5 into the equation and follow the order of operations: y = 2(5) + 1 = 11.

A square has four equal sides, so its perimeter is 4 × side length: 4 × 7 = 28.

The mean is the sum divided by the number of values: (4 + 8 + 12) / 3 = 24 / 3 = 8.

With an even count, the median is the average of the two middle values: (5 + 9) / 2 = 7.

Divide both sides by 5 to isolate x: 5x = 45 becomes x = 45 / 5 = 9.

Absolute value is the distance from zero on the number line, so |-12| = 12 even though -12 is negative.

The area of a circle is π times the radius squared: Area = π × 3^2 = 9π.

The volume of a cube is side cubed: Volume = 3 × 3 × 3 = 27 cubic units.

Multiplying both parts of 2:3 by 4 gives 8:12.

Convert 15% to 0.15 and multiply: 15% of 200 is 200 × 0.15 = 30.

Subtract 3 from 10 to isolate a: a + 3 = 10 becomes a = 10 - 3 = 7.

Since 4 × 4 × 4 = 64, the cube root of 64 is 4, so x = 4.

Use the formula distance = rate × time: 60 miles per hour × 2.5 hours = 150 miles.

1/3 ≈ 0.333, which is less than 0.4.

24 is divisible by 3 and by 4; the other choices are not.

3/5 = 6/10, and 6/10 + 1/10 = 7/10.

One favorable outcome out of six equally likely outcomes gives 1/6.

Divide the part by the total: 12 / 48 = 0.25, and multiplying by 100 gives 25%.

Add 6 to both sides to get 2x = 16, then divide by 2 to find x = 8.

The circumference of a circle is 2π times the radius: 2π × 5 = 10π.

Slope is the change in y divided by the change in x: (8 - 0) / (4 - 0) = 2.

Add the numbers in the numerator first: (7 + 13) / 5 = 20 / 5 = 4.

Convert 40% to 0.40 and multiply: 250 × 0.40 = 100.

Adding 1 to an odd integer always produces an even integer.

The largest factor shared by 18 and 24 is 6.

Write 0.125 as 125/1000, then simplify by dividing both numbers by 125 to get 1/8.

Substitute x = 3 into the function: f(3) = 3^2 + 1 = 9 + 1 = 10.

3, 7, and 11 are prime; 9 and 15 have more than two factors.

2, 8, and 14 are all even numbers, so each one is divisible by 2 without a remainder.

5 + 5, 20 / 2, and 2 × 5 all equal 10.

12, 18, and 24 are all multiples of 6, so each one is divisible by 6 without a remainder.

Scarce, sparse, and meager all describe a small amount, so they are similar in meaning even if the context differs.

Zeal means great energy or enthusiasm, so enthusiasm and passion fit.

Positive correlation means values increase together, shown by an upward trend.

Distributing gives 2x + 6, and multiplication is commutative, so (x + 3) × 2 is also equivalent.

Divide both sides by 3 to isolate x: 3x = 27 becomes x = 27 / 3 = 9.

The mean is the sum divided by the count: (5 + 10 + 15) / 3 = 30 / 3 = 10.

Multiply the numerator and denominator by 2 to get 4/10, which equals the decimal 0.4.

The area of a square is side squared: Area = 6 × 6 = 36 square units.

The pattern multiplies each term by 2: 6, 12, 24, so the next term is 24 × 2 = 48.

In the slope-intercept form y = mx + b, the coefficient m is the slope, so m = 4 here.

Ephemeral is short-lived, laconic is brief, pragmatic is practical, and erudite is scholarly.

Mean is the average, median is the middle value, mode is most frequent, and range is the difference between extremes.

Radius goes center to edge, diameter crosses through the center, circumference is the perimeter, and area is the enclosed space.

Slope is rate of change, intercepts are crossing points, and a constant is a fixed value.

Inference draws a conclusion, paraphrase restates, summary condenses, and evidence supports.

A variable is measured, a sample is a subset, an outlier is unusual, and a distribution shows spread.