GCSE MATH 3 — Questions and Answers
Question 1: Which of the following is a prime number?
- 51
- 57
- 59 (Correct answer)
- 63
Correct answer: 59
59 has no factors other than 1 and itself; 51 = 3×17, 57 = 3×19, 63 = 9×7.
Question 2: What is the nth term of the sequence 5, 9, 13, 17, 21, …?
- 4n + 1 (Correct answer)
- 5n − 1
- 4n + 5
- 3n + 2
Correct answer: 4n + 1
The common difference is 4 and the first term gives 4(1) + 1 = 5, confirming 4n + 1.
Question 3: A car travels 180 km in 2.5 hours. What is its average speed?
- 60 km/h
- 70 km/h
- 72 km/h (Correct answer)
- 80 km/h
Correct answer: 72 km/h
Speed = Distance ÷ Time = 180 ÷ 2.5 = 72 km/h.
Question 4: Simplify the ratio 48 : 36.
- 4:3 (Correct answer)
- 3:4
- 8:6
- 12:9
Correct answer: 4:3
Divide both by their HCF (12): 48/12 = 4 and 36/12 = 3, giving 4:3.
Question 5: If y = x² − 3x + 2, what is the value of y when x = 4?
- 2
- 4
- 6 (Correct answer)
- 8
Correct answer: 6
y = 16 − 12 + 2 = 6.
Question 6: What is the interior angle sum of a hexagon?
- 540°
- 720° (Correct answer)
- 900°
- 1080°
Correct answer: 720°
Sum of interior angles = (n − 2) × 180° = (6 − 2) × 180° = 720°.
Question 7: A price of $80 is increased by 35%. What is the new price?
- $100
- $108 (Correct answer)
- $112
- $116
Correct answer: $108
$80 × 1.35 = $108.
GCSE MATH 3
Which of the following is a prime number?