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.

1,431.

Simplify \(\sqrt{50} + \frac{10}{\sqrt{2}}\)

A.

10

B.

10\(\sqrt{2}\)

C.

20

D.

20\(\sqrt{2}\)

Correct answer is B

\(\sqrt{50} + \frac{10}}{\sqrt{2}} = \(\frac{\sqrt{50}}{1} + \sqrt{10}{\sqrt{2}}\)

= \(\frac{\sqrt{50 \times 2} + 10}{\sqrt{2}}\)

= \(\frac{\sqrt{100} + 10}{\sqrt{2}}\)

= \(\frac{10 + 10}{\sqrt{2} = \frac{20}{\sqrt{2}}\)

= \(\frac{20}{\sqrt{2}}\) \times \frac{\sqrt{2}}{\sqrt{2}}\)

= \(\frac{20\sqrt{2}}{2}\)

= 10\(\sqrt{2}\)

1,432.

Find the product of 0.0409 and 0.0021 leaving your answer in the standard form

A.

8.6 x 10-6

B.

8.6 x 105

C.

8.6 x 10-4

D.

8.6 x 10-5

Correct answer is D

0.0409 x 0.0021 = 409 x 10\(^{-4}\) x 21 x 10\(^{-4}\)

= 409 x 21 x 10\(^{-4 * -4}\)

= 8589 x 10\(^{-8}\)

= 8.589 x 10\(^{3}\) x 10\(^{-8}\)

= 8.6 x 10\(^{3-8}\)

= 8.6 x 10\(^{-5}\)

1,433.

Evaluate \(\frac{(3.2)^2 - (4.8)^2}{3.2 + 4.8}\)

A.

-0.08

B.

-1.60

C.

-10.24

D.

-12.80

Correct answer is B

\(\frac{(3.2)^2 - (4.8)^2}{3.2 + 1.8} = \frac{(3.2 - 4.8)(3.2 + 4.8)}{(3.2 + 4.8)}\)

= 3.2 - 4.8

= -1.60

1,434.

If x% of 240 equals 12, find x

A.

x = 1

B.

x = 3

C.

x = 5

D.

x = 7

Correct answer is C

x% of 240 = 12

\(\frac{x}{100} \times 240 = 12\)

x = \(\frac{12 \times 100}{240}\)

x = 5

1,435.

In the diagram, O is the centre of the circle and PQ is a diameter. Triangle RSO is an equilateral triangle of side 4cm. Find the area of the shaded region

A.

43.36cm2

B.

32.072

C.

18.212

D.

6.932

Correct answer is C

Area of shaded portion = Area of semicircle

Area of \(\bigtriangleup\) RSO

Area of semicircle = \(\frac {\pi r^2}{2} = \frac{22\times 4 \times 4}{7 \times 2}\)

= 25.14cm2; Area of \(\bigtriangleup\)RSO

=\(\sqrt{s(s - 1)(s - b)(s - c)}\); where

s = \(\frac{a + b + c}{2}\)

s = \(\frac{4 + 4 + 4}{2}\)

= 6cm

= \(\sqrt{6(6 - 4)(6 - 4) (6 - 4)}\)

= \(\sqrt{6(2) (2) (2)}\)

= \(\sqrt{18}\) = 6.93cm2

Area of shaded region

= 25.14 - 6.93

= 18.21cm2