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.

2,311.

If 3 gallons of spirit containing 20% water are added to 5 gallons of another spirit containing 15% water, what percentage of the mixture is water?

A.

2\(\frac{4}{5}\)%

B.

16\(\frac{7}{8}\)%

C.

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

D.

18\(\frac{7}{8}\)%

Correct answer is B

% of water in the mixture

= \(\frac{\text{Total Amount of water}}{\text{Total quantity of spirit}}\) x \(\frac{100}{1}\)

\(\frac{3(\frac{20}{100}) + 5 (\frac{15}{100})}{3 + 5}\) x \(\frac{100}{1}\)

= \(\frac{\frac{6}{10} + \frac{75}{100}}{8}\) x \(\frac{100}{1}\)

= \(\frac{0.6 + 0.75}{8}\) x \(\frac{100}{1}\)


= \(\frac{1.35}{8}\) x \(\frac{100}{1}\)

= \(\frac{33.75}{2}\)

= 16.875

= 16\(\frac{7}{8}\)

2,312.

Musa borrows N10.00 at 2% per month simple interest and repays N8.00 after 4 months. How much does he still owe?

A.

N10.80

B.

N10.67

C.

N2.80

D.

N2.67

Correct answer is C

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

= \(\frac{10 \times 2 \times 4}{100}\)

= \(\frac{4}{5}\)

= 0.8

Total amount = N10.80

He pays N8.00

Remainder = 10.80 - 8.00

= N2.80

2,313.

Factory P produces 20,000 bags of cement per day while factory Q produces 15,000 bags per day. If P reduces production by 5% and Q increases production by 5%, determine the effective loss in the number of bags produced per day by the two factories

A.

250

B.

750

C.

1000

D.

1250

Correct answer is A

P produces 20,000 bags

P reduces production by 5%

i.e. reduction = \(\frac{5}{100}\) x \(\frac{20000}{1}\)

= 1000

Q produces 15000 bags

Q increases production by 5%

i.e. increase = \(\frac{5}{100}\) x \(\frac{15000}{1}\)

= 750

Effective loss by the two = 1000 - 750

= 250 bags

2,314.

express 62 \(\div\) 3 as a decimal correct to 3 significant figures

A.

20.6

B.

20.667

C.

20.67

D.

20.7

Correct answer is D

\(\frac{62}{3}\) = 20.6666.....

= 20.7 to 3 sig. fig.

2,315.

Find correct to 3 decimal places (\(\frac{1}{0.05}\) + \(\frac{1}{5.005}\)) - (0.05 x 2.05)

A.

99.998

B.

98.999

C.

89.899

D.

9.998

Correct answer is A

(\(\frac{1}{0.05}\) + \(\frac{1}{5.005}\)) - (0.05 x 2.05)

(\(\frac{1}{0.05}\) x 5.005) - (0.05 x 2.05)


\(\frac{5.005}{0.05}\) - 0.1025

100.1 - 0.1025

= 99.9975

99.998 to 3 decimal place.