Mixed Deck — All GMAT Topics Flashcards

What is the area of a triangle with base 10 and height 6?

Answer: 30

Area of a triangle = ½ × base × height = ½ × 10 × 6 = 30.

In a class of 40, 25 study French and 20 study Spanish. If 8 study both, how many study only French?

Answer: 17

Only French = 25 − 8 = 17.

Set A = {1, 2, 3, 4, 5} and Set B = {3, 4, 5, 6, 7}. What is |A∪B| − |A∩B|?

Answer: 4

A∩B = {3,4,5}, |A∩B| = 3. A∪B = {1,2,3,4,5,6,7}, |A∪B| = 7. 7 − 3 = 4.

Using the same rental formula, the mileage giving an $80 total is:

Answer: 200

30 + 0.25m = 80 gives 0.25m = 50, so m = 200.

If $5000 is invested at simple interest and grows to $5900 in 3 years, what is the annual interest rate?

Answer: 6%

Interest is $900 over 3 years on $5000, so rate = 900/(5000×3) = 6%.

The angles of a triangle are in the ratio 1:2:3. What is the measure of the largest angle?

Answer: 90°

The angles sum to 180°; with ratio 1:2:3 (6 total parts), each part = 30°, so the largest angle = 3 × 30° = 90°.

A multi-source reasoning question: A research paper says Drug X reduces blood pressure by 15 mmHg on average. A clinical trial report notes that 20% of Drug X patients experienced side effects. From this, what is the best integrated conclusion?

Answer: Drug X shows meaningful blood pressure reduction but side effect frequency should be factored into prescribing decisions

Both pieces of information are relevant: the efficacy (15 mmHg reduction) and the safety profile (20% side effects). A balanced clinical conclusion considers both without dismissing either.

If x:y = 9:4, what is the ratio of x^2 to y^2?

Answer: 81:16

Squaring both terms gives 81:16.

An ad claims a supplement boosts memory because users scored higher on a test after taking it. What assumption does this rely on?

Answer: No other factor caused the score improvement

The causal claim assumes the supplement, not some confounding factor, produced the gain.

A study found that people who regularly drink at least one cup of green tea daily have a lower incidence of heart disease than people who do not. The study's authors concluded that the compounds in green tea are directly responsible for a reduced risk of heart disease.

Answer: Individuals who regularly drink green tea are also significantly more likely to engage in other healthy lifestyle behaviors, such as regular exercise and a balanced diet.

This statement weakens the argument by introducing a potential alternative cause for the observed outcome. If green tea drinkers are also more likely to exercise and eat well, then these other behaviors, rather than the green tea itself, could be the reason for their lower incidence of heart disease. This breaks the direct causal link the author asserts between green tea and heart health, which is a classic correlation vs. causation flaw.

Argument: 'Teenagers who spend more than 3 hours per day on social media report higher rates of anxiety and depression. Therefore, limiting social media use among teenagers to under 3 hours per day will improve their mental health.' Which of the following most accurately describes a flaw in the reasoning above?

Answer: The argument assumes that heavy social media use causes poor mental health rather than the reverse

Teenagers experiencing anxiety or depression may turn to social media more as a coping mechanism (reverse causation) — the mental health issues may be causing the heavy usage rather than the usage causing the mental health issues.

Argument: 'A nutritional study found that people who eat breakfast every day have lower rates of obesity than those who skip breakfast. Public health campaigns should therefore encourage daily breakfast consumption to combat obesity.' Which of the following, if true, would most strengthen this argument?

Answer: Breakfast skippers tend to eat larger meals later in the day, consuming more total calories

A provides a plausible mechanism: breakfast prevents overeating later, establishing a causal link between breakfast consumption and lower caloric intake that could reduce obesity.

Argument: 'Vegetarians have been found to have lower rates of heart disease than meat-eaters. Therefore, eliminating meat from one's diet will reduce heart disease risk.' To evaluate this argument, it would be most important to determine:

Answer: Whether vegetarians differ from meat-eaters in other lifestyle factors such as exercise, smoking, and alcohol use

Vegetarians may also exercise more, smoke less, and drink less alcohol — the lower heart disease rate may reflect their overall healthier lifestyle, not specifically their meat avoidance.

What is the best general strategy for Two-Part Analysis questions involving algebraic conditions?

Answer: Translate each condition into an equation and test the column values

Setting up equations for each part and testing the shared options reliably identifies both answers.

A nonprofit claims its campaign raised awareness because website visits doubled. This assumes that:

Answer: The visit increase came from the campaign, not an unrelated event

Attributing the rise to the campaign assumes no other driver of traffic.

Multi-Source Reasoning: a budget tab allocates $10,000 total and a spending tab lists expenses of $4,000, $3,000, and $2,000. The remaining budget is:

Answer: $1,000

Total spending is $9,000, leaving $10,000 − $9,000 = $1,000.

Passage: 'The discovery of the double-helix structure of DNA by Watson and Crick in 1953 — building on X-ray crystallography images produced by Rosalind Franklin — is among the most celebrated achievements in the history of science. The structure immediately suggested a mechanism for genetic replication: the two complementary strands could separate and serve as templates for new molecules. Subsequent decades saw the development of recombinant DNA technology, the polymerase chain reaction, and ultimately the sequencing of the human genome — all downstream consequences of understanding DNA's structure. Historians of science have since examined the degree to which Franklin's contributions were acknowledged during her lifetime, finding that recognition was substantially delayed.' The passage's reference to Rosalind Franklin serves primarily to:

Answer: Note that the discovery depended on prior work and that proper credit was delayed

Franklin is mentioned to acknowledge that the discovery 'built on' her work (showing dependence on prior research) and that 'recognition was substantially delayed' (noting credit issues).

A heat map uses darker shading for higher values. A nearly all-light row indicates that category has:

Answer: Consistently low values

Light shading throughout a row indicates low values across all columns for that category.

What is the sum of the first 10 positive integers?

Answer: 55

Using n(n+1)/2 = 10×11/2 = 55.

An author argues a critic's position is self-contradictory. This method of reasoning is:

Answer: Exposing an internal inconsistency

Showing a position contradicts itself attacks it by internal inconsistency.