Mathematics 2017 Past Questions | WAEC
Study the following Mathematics past questions and answers for JAMB, WAEC NECO and Post-JAMB. Get prepared with official past questions and answers for upcoming examinations.
11. Solve: – \(\frac{1}{4}\) < \(\frac{3}{4}\) (3x – 2) < \(\frac{1}{2}\)
- A. -\(\frac{5}{9}\) < x <\(\frac{8}{9}\)
- B. -\(\frac{8}{9}\) < x <\(\frac{7}{9}\)
- C. -\(\frac{8}{9}\) < x <\(\frac{5}{9}\)
- D. -\(\frac{7}{9}\) < x <\(\frac{8}{9}\)
Correct Option: Answer is A
\(\frac{3}{4}\) (3x – 2) < \(\frac{1}{2}\); \(\frac{3}{4}\) (3x – 2) > – \(\frac{1}{4}\)
3(3x – 2) < 2; 3(3x – 2) > -1
9x – 6 < 2; 9x – 6 > -1
9x < 8; 9x > 5
x < \(\frac{5}{9}\); x > \(\frac{8}{9}\)
12. Simplify; 3x – (p – x) – (r – p)
- A. 2x – r
- B. 2x + r
- C. 4x – r
- D. 2x – 2p – r
Correct Option: Answer is C
3x – (p – x) – ( r – p)
= 3x – p + x – r + p
= 4x – r
13. An arc of a circle of radius 7.5cm is 7.5cm long. Find, correct to the nearest degree, the angle which the arc subtends at the centre of the circle. [Take π=22/7]
- A. 29o
- B. 57o
- C. 65o
- D. 115o
Correct Option: Answer is B
lac = \(\frac{\theta}{360}\) x 2\(\pi\)r
7.5 = \(\frac{\theta}{360}\) x 2 x \(\frac{22}{7}\) x 7.5
7.5 = \(\frac{330\theta}{2520}\)
\(\theta\) = \(\frac{7.5}{0.1309}\)
\(\theta\) = 57.29
\(\theta\) = 57 \(^o\)
14. Water flows out of a pipe at a rate of 40πcm2 per seconds into an empty cylinder container of base radius 4cm. Find the height of water in the container after 4 seconds.
- A. 10 cm
- B. 14 cm
- C. 16 cm
- D. 20 cm
Correct Option: Answer is A
Volume of a cylinder = πr²h
40πcm³ = π.4²h
40cm³= 16h
h = 2.5cm/sec
In 4 seconds, 2.5cm x 4
= 10cm
15. The dimensions of water tank are 13cm, 10cm and 70cm. If it is half-filled with water, calculate the volume of water in litres
- A. 4.55 litres
- B. 7.50 litres
- C. 8.10 litres
- D. 9.55 litres
Correct Option: Answer is A
Vol of a cubiod = L x b x h
v = 13cm x 10cm x 70cm
= 9100cm
Since it is half-filled = 9100/cm
= 4550cm
4550cm → 4.55 litres
16. If the total surface area of a solid hemisphere is equal to its volume, find the radius
- A. 3.0cm
- B. 4.5cm
- C. 5.0cm
- D. 9.0cm
Correct Option: Answer is B
T.S.A of hemisphere = 3\(\pi r^2\)
vol of hemisphere = \(\frac{2}{3} \pi r^2\)
3\(\pi r^2\) = \(\frac{2}{3} \pi r^2\)
3 = \(\frac{2}{3} \pi r\)
9 = 2r
r = \(\frac{9}{2}\)
r = 4.5cm
17. Which of the following is true about parallelogram?
- A. opposite angles are supplementary
- B. opposite angles are complementary
- C. opposite angles are equal
- D. opposite angles are reflex angles
Correct Option: Answer is C
18. Calculate the gradient (slope) of the joining points (-1, 1) and (2, -2)
- A. -1
- B. −1/2
- C. 12
- D. 1
Correct Option: Answer is A
19. If P(2,3) and Q)2, 5) are points on a graph, calculate the length PQ
- A. 6 units
- B. 5 units
- C. 4 units
- D. 2 units
Correct Option: Answer is D
\(\sqrt{(x_2 – x_1)^2 + (y_2 – Y_1)^2}\)
= \(\sqrt{(2 – 2)^2 + (5 – 3)^2}\)
= \(\sqrt{0^2 + 2^2}\)
= \(\sqrt{4}\)
= 2 units
20. A bearing of 320º expressed as a compass bearing is
- A. N 50º W
- B. N 40º W
- C. N 50º E
- D. N 40o E