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.

2,141.

Find m such that (m + \(\sqrt{3}\))(1 - \(\sqrt{3}\))2 = 6 - 2\(\sqrt{2}\)

A.

1

B.

2

C.

3

D.

4

Correct answer is C

(m + \(\sqrt{3}\))(1 - \(\sqrt{3}\))2 = 6 - 2\(\sqrt{2}\)

(m + \(\sqrt{3}\))(4 - 2\(\sqrt{3}\)) = 6 - 2\(\sqrt{2}\)

= 6 - 2\(\sqrt{3}\)

4m - 6 + 4 - 2m\(\sqrt{3}\) = 6 - 2\(\sqrt{3}\)

comparing co-efficients,

4m - 6 = 6.......(i)

4 - 2m = -2.......(ii)

in both equations, m = 3

2,142.

If \(log_{10} 2 = 0.3010\) and \(log_{10} 3 = 0.4771\), evaluate; without using logarithm tables, \(log_{10} 4.5\)

A.

0.3010

B.

0.4771

C.

0.6532

D.

0.9542

Correct answer is C

If \(log_{10} 2 = 0.3010\) and \(log_{10} 3 = 0.4771\),

\(\log_{10} 4.5 = \log_{10}  (\frac{3 \times 3}{2})\)

\(log_{10} 3 + log_{10} 3 - log_{10} 2 = 0.4771 + 0.4771 - 0.3010\)

= 0.6532

2,143.

Evaluate \(\frac{8^{\frac{1}{3}} \times 5^{\frac{2}{3}}}{10^{\frac{2}{3}}}\) 

A.

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

B.

\(\frac{5}{3}\)

C.

3\(\sqrt{5}\)

D.

3\(\sqrt{2}\)

Correct answer is D

\(\frac{8^{\frac{1}{3}} \times 5^{\frac{3}{2}}}{\frac{2}{10^3}}\) = \(\frac{(2^3)^{\frac{1}{3}} \times 5^{\frac{3}{2}}}{(2 \times 5)^{\frac{2}{3}}}\)

= \(\frac{2 \times 5}{2^{\frac{2}{3}} \times 5^{\frac{3}{2}}}\)

= 21 - \(\frac{2}{3}\)

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

= 3\(\sqrt{2}\)

2,144.

A tax payer is allowed \(\frac{1}{8}\)th of his income tax-free, and pays 20% on the remainder. If he pays N490.00 tax, what is his income?

A.

N560.00

B.

N2,450.00

C.

N2,800.00

D.

N3,920.00

Correct answer is C

He pays tax on 1 - \(\frac{1}{8}\) = \(\frac{7}{8}\)th of his income

20% is 490, 100% is \(\frac{100}{20}\) x 490, N2,450.00

= \(\frac{7}{8}\) of his income = N2,450.00


\(\frac{1}{\frac{7}{8}}\) x 2450

= \(\frac{8 \times 2450}{7}\)

= \(\frac{19600}{7}\)

= N2800.00

2,145.

A basket contain green, black and blue balls in the ratio 5 : 2 : 1. If there are 10 blue balls. Find the corresponding new ratio when 10 green and 10 black balls are removed from the basket

A.

1 : 1 : 1

B.

4 : 2 : 1

C.

5 : 1 : 1

D.

4 : 1 : 1

Correct answer is D

Let x represent total number of balls in the basket.

If there are 10 blue balls, \(\frac{1}{8}\) of x = 10

x = 10 x 8 = 80 balls

Green balls will be \(\frac{5}{8}\) x 80 = 50 and black balls = \(\frac{2}{8}\) x 80 = 20

Ratio = Green : black : blue

50 : 20 : 10

-10 : -10 : -
------------------
New Ratio 40 : 10 : 10

4 : 1 : 1