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.

1,461.

P naira invested for 4 years invested for 4 years at r% simple interest per annum yields 0.36 p naira interest. Find the value of r

A.

1\(\frac{1}{9}\)

B.

1\(\frac{4}{9}\)

C.

9

D.

11

Correct answer is C

I = \(\frac{PRT}{100}\)

where r = r% p.a; I = 0.36p

0.36p = \(\frac{P \times r \times 4}{100}\)

\(\frac{0.36 \times 100}{4}\) = r

r = 9

1,462.

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\(\sqrt{2}\)

1,463.

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\(^{-5}\)

1,464.

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

1,465.

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