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.

1,936.

Simplify \(\frac{3}{2x - 1}\) + \(\frac{2 - x}{x - 2}\)

A.

\(\frac{2 - x}{(2x - 1)(x - 2)}\)

B.

\(\frac{5 - x}{(2x - 1)(x - 2)}\)

C.

\(\frac{4 - 2x}{2x - 1}\)

D.

\(\frac{6 - 3x}{(2x - 1)(x - 2)}\)

Correct answer is C

\(\frac{3}{2x - 1}\) + \(\frac{2 - x}{x - 2}\)

= \(\frac{3}{2x - 1}\) - \(\frac{x - 2}{x - 2}\)

= \(\frac{3}{2x - 1}\) - 1

= \(\frac{3 - (2x - 1)}{2x - 1}\)

= \(\frac{3 - 2x + 1}{2x - 1}\)

= \(\frac{4 - 2x}{2x - 1}\)

1,937.

In a regular polygon of n sides, each interior angle is 144°. Find n

A.

12

B.

11

C.

10

D.

8

E.

6F

Correct answer is C

Formula for an interior angle of a polygon is (2n - 4) x 90

(2n - 4) x 90 = 144n

190n - 360 = 144n

n = \(\frac{360}{36}\)

= 10

1,938.

The diameter of a metal rod is measured as 23.40 cm to four significant figures. What is the maximum error in the measurement?

A.

0.05cm

B.

0.5cm

C.

0.045cm

D.

0.005cm

E.

0.004cm

Correct answer is D

Maximum error in measurement to 2 decimal places

Maximum error = \(\frac{1}{2}\) x 0.001

= 0.005

1,940.

If \(\frac{3e + f}{3f - e}\) = \(\frac{2}{5}\), find the value of \(\frac{e + 3f}{f - 3e}\)

A.

\(\frac{5}{2}\)

B.

1

C.

\(\frac{26}{7}\)

D.

\(\frac{1}{3}\)

Correct answer is C

\(\frac{3e + f}{3f - e}\) = \(\frac{2}{5}\)

= 3e + f

= 2 x 1

\(\frac{-e + 3f}{3e - f}\) = \(\frac{5 \times 3}{2}\)

= \(\frac{3e + 9f = 15}{10f = 17}\)

f = \(\frac{17}{10}\)

Sub. for equ. (1)

3e + \(\frac{17}{10}\) = 2

3e = 2 - \(\frac{17}{10}\)

\(\frac{3}{10}\)

e = \(\frac{3}{10}\) x \(\frac{1}{3}\)

= \(\frac{1}{10}\)

= e + 3f = \(\frac{1}{10}\) + \(\frac{3 \times}{10}\) = \(\frac{52}{10}\)

f - 3e = \(\frac{17}{10}\) - 3 x \(\frac{1}{10}\)

= \(\frac{14}{10}\)

= \(\frac{52}{10}\) x \(\frac{10}{14}\)

= \(\frac{26}{7}\)