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.

2,706.

Calculate the time taken for N3000 to earn N600 if invested at 8% simple interest

A.

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

B.

3 years

C.

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

D.

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

Correct answer is A

Using \(S.I =\frac{P \times T \times R}{100}\)

\(600 =\frac{3000 \times T \times 8}{100}\)

\(T =\frac{600 \times 100}{3000 \times 8}\)

\(\frac{20}{8}\)

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

2,707.

Evaluate \(\frac{1.25 \times 0.025}{0.05}\), correct to 1 decimal place

A.

0.6

B.

6.2

C.

6.3

D.

0.5

Correct answer is A

\(\frac{1.25 \times 0.025}{0.05}\)

\( = \frac{125 \times 10^{-2} \times 25 \times 10^{-3}}{5 \times 10^{-2}}\)

= 125 x 5 x 10-3

= 625 x 0.001

= 0.625

= 0.6 Approx to 1 d.p.

2,708.

3 girls share a number of apples in the ration 5:3:2. If the highest share is 40 apples, find the smallest share

A.

36

B.

24

C.

16

D.

38

Correct answer is C

The sum, S of ratio is S = 5 + 3 + 2 = 10.

But highest share = \(\frac{5}{10} \times T\), where T is the total number of apples.

Thus, \(40 = \frac{5}{10} \times T\),

given 40 x 10 = 5T,

\(T = \frac{40 \times 10}{5} = 80\)

Hence the smallest share = \(\frac{2}{10} \times 80\)

= 16 apples

2,709.

Convert 2710 to another number in base three

A.

10013

B.

10103

C.

11003

D.

10003

Correct answer is D

\(\begin{array}{c|c}
3 & \text{27 rem 0} \\
\hline
3 & \text{ 9 rem 0} \\
\hline
3 & \text{ 3 rem 0} \\
\hline
3 & \text{ 1 rem 1}\\
\hline
& 0
\end{array}\)

Hence the correct answer is 10003

2,710.

A number is chosen at random from 10 to 30 both inclusive. What is the probability that the number is divisible by 3?

A.

\(\frac{2}{15}\)

B.

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

C.

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

D.

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

Correct answer is C

Sample space S = {10, 11, 12, ... 30}

Let E denote the event of choosing a number divisible by 3

Then E = {12, 15, 18, 21, 24, 27, 30} and n(E) = 7

Prob (E) = \(\frac{n(E)}{n(S)}\)

Prob (E) = \(\frac{7}{21}\)

Prob (E) = \(\frac{1}{3}\)