Mathematics questions and answers

Mathematics Questions and Answers

How good are you with figures and formulas? Find out with these Mathematics past questions and answers. This Test is useful for both job aptitude test candidates and students preparing for JAMB, WAEC, NECO or Post UTME.

1,201.

An open cone with base radius 28cm and perpendicular height 96cm was stretched to form sector of a circle. calculate the arc of the sector (Take \(\pi = \frac{22}{7}\))

A.

8800cm2

B.

8448cm2

C.

4400cm2

D.

4224cm2

Correct answer is A

L2 = 962 + 282

= 9216 + 784

= 10000

L = \(\sqrt{10000}\)

= 100cm

curved surface area = \(\pi r l\)

= \(\frac{22}{7} \times 28 \times 100\)

= 8800cm2

area of cone = area of sector

area of sector = 8800cm2

1,202.

Given that (x + 2)(x2 - 3x + 2) + 2(x + 2)(x - 1) = (x + 2) M, find M

A.

(x + 2)2

B.

x(x + 2)

C.

xv + 2

D.

x2 - x

Correct answer is D

(x = 2)(x2 - 3x + 2) + 2(x + 2)(x - 1) = (x + 2)m

(m + 2)[(x2 - 3x + 2) + 2(x - 1)] = (x + 2)M

divide both side by (x + 2)

(x2 - 3x + 2) + 2(x - 1) = M

x2 - 3x + 2 + 2x - 2 = M

x2 - 3x + 2 + 2x - 2 = M

x2 - 3x + 2x = M

x2 - x = M

M = x2 - x

1,203.

The distance between two towns is 50km. It is represented on a map by 5cm. Find the scale used

A.

1: 1,000,000

B.

1: 500,000

C.

1: 100,000

D.

1: 10,000

Correct answer is A

1km = 100,000cm

on the map 1 cm represent every 10 km which is equal to (10 x 100,000cm)

= 1,000,000cm

the scale is 1:1,000,000

1,204.

The slant height of a cone is 5cm and the radius of its base is 3cm. Find, correct to the nearest whole number, the volume of the cone. ( Take \(\pi = \frac{22}{7}\))

A.

48cm3

B.

47cm3

C.

38cm3

D.

12cm3

Correct answer is C

Volume of a cone = \(\frac{1}{3} \pi r^2h\)

h2 = 52 = 32

= 25 - 9 = 16

h = \(\sqrt{16}\)

h = 4cm

v = \(\frac{1}{3} \times \frac{22}{7} \times 3^2 \times 4\)

\(\frac{1}{3} \times \frac{22}{7} \times 9 \times 4\)

= \(\frac{22 \times 3 \times 4}{7}\)

= 37.7cm3

= 38cm3

1,205.

A pyramid has a rectangular base with dimensions 12m by 8m. If its height is 14m, calculate the volume

A.

322m3

B.

448m3

C.

632m2

D.

840m2

Correct answer is B

Volume of pyramid = \(\frac{1}{3}\) x base area x height

= \(\frac{1}{3} \times 12^4 \times 8 \times 14\)

= 4 x 8 x 14 = 448m3