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.

2,146.

Simplify without using tables \(\frac{2\sqrt{14} \times 3\sqrt{21}}{7\sqrt{24} \times 2\sqrt{98}}\)

A.

\frac{3\sqrt{14}}{4}\)

B.

\(\frac{3\sqrt{2}}{4}\)

C.

\(\frac{3\sqrt{14}}{28}\)

D.

\(\frac{3\sqrt{2}}{28}\)

Correct answer is D

\(\frac{2\sqrt{14} \times 3\sqrt{21}}{7 \sqrt{24} \times 2\sqrt{98}}\) = \(\frac{6\sqrt{14} \times 3 \times \sqrt{7} \times \sqrt{3}}{7 \times 2 \sqrt{6} \times \sqrt{7} \times \sqrt{14}}\)

= \(\frac{3\sqrt{3}}{14\sqrt{6}}\)

= \(\frac{3\sqrt{3}}{14\sqrt{2} \times \sqrt{3}}\)



= \(\frac{3\sqrt{2}}{28}\)

2,147.

Simplify without using tables \(\frac{log_26}{log_28}\) - \(\frac{log_23}{2log_2\frac{1}{2}}\)

A.

\(\frac{1}{5}\)

B.

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

C.

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

D.

(\frac{log_23}{log_27}\)

Correct answer is A

log\(_2\)6 - log\(_2\)3 = log\(_2\) (\(\frac{6}{3}\))

= log\(_2\)2... A

log\(_2\)8 - 2log\(_2\)\(\frac{1}{2}\)

log\(_2\)8 - log\(_2\)\(\frac{1}{2}\)\(^2\)

log\(_2\)8 - log\(_2\)\(\frac{1}{4}\)

= log\(_2\) 32... B

\(\frac{A}{B}\) = \(\frac{log_22}{log_232}\)

N.B. log\(_2\)2 = 1

= \(\frac{1}{5}\)
 

2,148.

Evaluate without using tables (0.008) -\(\frac{1}{3}\) x (0.16) - \(\frac{3}{2}\)

A.

\(\frac{625}{8}\)

B.

\(\frac{8}{625}\)

C.

\(\frac{1}{8}\)

D.

8

Correct answer is A

(0.008) -\(\frac{1}{3}\) x (0.16) - \(\frac{3}{2}\) = (8 x 10-3)10-3 x (16 x 10-2)-\(\frac{3}{2}\)

= \(\frac{(2^3)}{10^3}\) - 3 x \(\frac{(2^4)}{10}\) - \(\frac{-3}{2}\)

= \(\frac{625}{8}\)

2,149.

Four boys and ten girls can cut a field in 5 hours if the boys work at \(\frac{5}{4}\) the rate at which the girls work. How many boys will be needed to cut the field in 3 hours?

A.

180

B.

60

C.

25

D.

20

Correct answer is D

Let x represents number of boys that can work at \(\frac{5}{4}\) the rate at which the 10 girls work

For 1hr. x boys will work for \(\frac{\frac{1}{5}}{4}\) x 10

x = \(\frac{4}{5}\) x 10 = 8 boys

8 boys will do the work of ten girls at the same rate 4 + 8 = 12 boys cut the field in 5 hrs

For 3 hrs, \(\frac{12 \times 5}{3}\) boys will be needed = 20 boys

2,150.

By selling 20 oranges for N1.35 a trader makes a profit of 8%. What is his percentage gain or loss if he sells the same 20 oranges for N1.10?

A.

8%

B.

10%

C.

12%

D.

15%

Correct answer is C

profit 8% of N1.35 = \(\frac{8}{100}\) x N1.35 = N0.08

Cost price = N1.35 - N0.10 = N1.25

If he sells the 20 oranges for N1.10 now

%loss = \(\frac{\text{actual loss}}{\text{Cost price}}\) x 100

\(\frac{125 - 1.10}{1.25}\) x 100

= \(\frac{0.15 \times 100}{1.25}\)

= \(\frac{15}{1.25}\)

= 12%