O-Level Mathematics 4 — Questions and Answers
Question 1: Find the value of x: 5(x - 2) = 3x + 4
- 5
- 6
- 7 (Correct answer)
- 8
Correct answer: 7
5x - 10 = 3x + 4 → 2x = 14 → x = 7.
Question 2: What is the equation of a line with gradient 3 and y-intercept -2?
- y = -2x + 3
- y = 3x + 2
- y = 3x - 2 (Correct answer)
- y = -3x + 2
Correct answer: y = 3x - 2
Using y = mx + c: gradient m = 3, y-intercept c = -2, so y = 3x - 2.
Question 3: A map has a scale of 1:50000. A distance of 4 cm on the map represents how many km in real life?
- 1 km
- 2 km (Correct answer)
- 4 km
- 5 km
Correct answer: 2 km
4 cm × 50000 = 200000 cm = 2000 m = 2 km.
Question 4: Calculate the circumference of a circle with diameter 14 cm. (Use π ≈ 22/7)
- 44 cm (Correct answer)
- 88 cm
- 22 cm
- 66 cm
Correct answer: 44 cm
C = πd = (22/7) × 14 = 44 cm.
Question 5: Solve the simultaneous equations: x + y = 7 and x - y = 3
- x=4, y=3
- x=5, y=2 (Correct answer)
- x=3, y=4
- x=6, y=1
Correct answer: x=5, y=2
Adding: 2x = 10, x = 5. Substituting: 5 + y = 7, y = 2.
Question 6: What type of triangle has all sides equal and all angles equal to 60°?
- Isosceles
- Scalene
- Equilateral (Correct answer)
- Right-angled
Correct answer: Equilateral
An equilateral triangle has all three sides equal and all three interior angles equal to 60°.
O-Level Mathematics 4
Find the value of x: 5(x - 2) = 3x + 4