GRE Practice Questions — All Questions

A circle has a radius of 5. What is its area, in terms of pi?

• a.20 pi
• b.25 pi✓
• c.15 pi
• d.10 pi

Area = pi x radius squared = pi x 5 squared = 25 pi.

A right triangle has legs of length 6 and 8. What is the length of its hypotenuse?

• a.14
• b.9
• c.12
• d.10✓

By the Pythagorean theorem, hypotenuse squared = 6 squared + 8 squared = 36 + 64 = 100, so the hypotenuse = 10. This is the well-known 6-8-10 triangle.

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

• a.80 degrees
• b.90 degrees✓
• c.60 degrees
• d.120 degrees

The ratio has 1 + 2 + 3 = 6 parts, and the angles sum to 180 degrees, so each part is 180 / 6 = 30 degrees. The largest angle is 3 parts = 3 x 30 = 90 degrees.

The mean (average) of five numbers is 12. What is their sum?

• a.12
• b.60✓
• c.17
• d.50

Mean = sum / count, so sum = mean x count = 12 x 5 = 60.

What is the median of the data set 4, 8, 8, 10, 20?

• a.10
• b.4
• c.12
• d.8✓

The values are already in order, and there are five of them, so the median is the third value. The third value is 8.