# 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$\pi c{m}^{2}$ 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$\pi .$

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/$\frac{2}{}$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