GMAS Mathematics 3 — Questions and Answers
Question 1: Solve for x: 3x − 7 = 14
- x = 3
- x = 5
- x = 7 (Correct answer)
- x = 9
Correct answer: x = 7
Add 7 to both sides to get 3x = 21, then divide by 3 to get x = 7.
Question 2: A circle has a radius of 5 cm. What is its circumference? (Use π ≈ 3.14)
- 15.70 cm
- 31.40 cm (Correct answer)
- 78.50 cm
- 25.12 cm
Correct answer: 31.40 cm
Circumference = 2πr = 2 × 3.14 × 5 = 31.40 cm.
Question 3: Which number is NOT a prime number?
- 11
- 17
- 21 (Correct answer)
- 23
Correct answer: 21
21 = 3 × 7, so it has factors other than 1 and itself, making it composite.
Question 4: What is 15% of 200?
- 20
- 25
- 30 (Correct answer)
- 35
Correct answer: 30
15% of 200 = 0.15 × 200 = 30.
Question 5: A bag contains 3 red, 5 blue, and 2 green marbles. What is the probability of randomly picking a blue marble?
- 1/2 (Correct answer)
- 1/4
- 3/10
- 5/9
Correct answer: 1/2
There are 5 blue marbles out of 10 total, so P = 5/10 = 1/2.
Question 6: Which expression represents 'four more than twice a number n'?
- 4n + 2
- 2n − 4
- 2n + 4 (Correct answer)
- 4n − 2
Correct answer: 2n + 4
'Twice a number n' is 2n, and 'four more than' means adding 4, giving 2n + 4.
Question 7: Two angles are supplementary. One angle measures 65°. What is the measure of the other angle?
- 25°
- 35°
- 115° (Correct answer)
- 125°
Correct answer: 115°
Supplementary angles add to 180°, so the other angle = 180° − 65° = 115°.
