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.

771.

A sphere of radius rcm has the same volume as cylinder of radius 3cm and height 4cm. Find the value of r

A.

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

B.

2

C.

3

D.

6

Correct answer is C

Volume of sphere = Volume of cylinder

i.e. \(\frac{4}{3} \pi r^3 = \pi r^2 h\)

\(\frac{4}{3} \pi r^3 = \pi \times 3^2 \times 4\)

r3 = \(\frac{\pi \times 9 \times 4 \times 3}{4 \pi}\)

r = 3\(\sqrt{27}\)

= 3

772.

If log2(3x - 1) = 5, find x.

A.

2.00

B.

3.67

C.

8.67

D.

11

Correct answer is D

Log2(3x - 1) = 5

Log2(3x - 1) = Log225

Log2(3x - 1) = Log232

3x - 1 = 32

3x = 32 + 1 = 33

x = \(\frac{33}{3}\)

= 11

773.

The marks of eight students in a test are: 3, 10, 4, 5, 14, 13, 16 and 7. Find the range

A.

16

B.

14

C.

13

D.

11

Correct answer is C

First, arrange the marks in order of magnitude; 3, 4, 5, 7, 10, 13, 14, 16

Hence range = 16 - 3 = 13

774.

A fair die is thrown two times. What is the probability that the sum of the scores is at least 10?

A.

\(\frac{5}{36}\)

B.

\(\frac{1}{6}\)

C.

\(\frac{5}{18}\)

D.

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

Correct answer is B

\(\begin{array}{c|c}
& 1 & 2 & 3 & 4 & 5 & 6 \\
\hline
1 & 1,1 & 1,2 & 1,3 & 1,4 & 1,5 & 1,6 \\ \hline 2 & 2,1 & 2,2 & 2,3 & 2,4 & 2,5 & 2,6 \\ \hline 3 & 3,1 & 3,2 & 3,3 & 3,4 & 3,5 & 3,6 \\ \hline 4 & 4,1 & 4,2 & 4,3 & 4,4 & 4,5 & 4,6 \\ 5 & 5,1 & 5,2 & 5,3 & 5,4 & 5,5 & 5,6 \\ \hline 6 & 6,1 & 6,2 & 6,3 & 6,4 & 6,5 & 6,6\end{array}\)

From the table above, event space, n(E) = 6

sample space, n(S) = 36

Hence, probability sum of scores is at least 10, is;

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

= \(\frac{6}{36}\)

= \(\frac{1}{6}\)

775.

The figure is a pie chart which represents the expenditure of a family in a year. If the total income of the family was Le 10,800,000.00, how much was spent on food?

A.

Le 2,250,000.00

B.

Le 22,700,000.00

C.

Le 3,600,000.00

D.

Le 4,500,000.00

Correct answer is C

sectoral angle representing food

= 360o - (80 + 70 + 90)o

= 120o

Amount spent on food

= \(\frac{\tect{sectoral angle}}{360^o}\) x Le 10,800,000

= Le 3,600,000