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.

1,321.

If a number is chosen at random from the set {x: 4 \(\leq x \leq 15\)}. Find the probability that it is a multiple of 3 or a multiple of 4

A.

\(\frac{1}{12}\)

B.

\(\frac{5}{12}\)

C.

\(\frac{7}{12}\)

D.

\(\frac{11}{12}\)

Correct answer is C

set = 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15

multiple of 3 = 6, 9, 12, 15

multiple of 4 = 4, 8, 12

Prob(multiple of 3 or 4) = Prob(multiple of 3) + pro(multiple of 4)

= \(\frac{4}{12} + \frac{3}{12} = \frac{7}{12}\)

1,322.

Solve the equation; 3x - 2y = 7, x + 2y = -3

A.

x = 1, y = -2

B.

x = 1, y = 3

C.

x = -2, y = -1

D.

x = 4, y = -3

Correct answer is A

3x - 2y = 7; Solve by elimination method

x + 2y = -3

3x - 2y = 7.....(i)

-3x + 6y = -9.....(ii)

-8y = 16

y = \(\frac{16}{-8} = -2\)

Put y = -2 into equation (i); 3x - 2y = 7

3x - 2(-2) = 7

3x + 4 = 7

3x = 7 - 4

3x = 3

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

1,323.

Given that cos xo = \(\frac{1}{r}\), express tan x in terms of r

A.

\(\frac{1}{\sqrt{r}}\)

B.

\(\sqrt{r}\)

C.

\(\sqrt{r^2 + 1}\)

D.

\(\sqrt{r^2 - 1}\)

Correct answer is D

cos xo = \(\frac{1}{r}\); \(\sqrt{r^2 - 1}\)

By Pythagoras r2 = 12 + x2 - 1

x = \(\sqrt{r^2 - 1}\)

tan xo = \(\sqrt{r^2 - 1}\)

= \(\sqrt{r^2 - 1}\)

1,324.

Solve for x in the equation; \(\frac{3}{5}\)(2x - 1) = \(\frac{1}{4}\)(5x - 3)

A.

zero

B.

1

C.

2

D.

3

Correct answer is D

\(\frac{3}{5}\)(2x - 1) = \(\frac{1}{4}\)(5x - 3)

\(\frac{6x}{5} - \frac{3}{5} = \frac{5x}{4} - \frac{3}{4}\)

\(\frac{6x}{5} - \frac{5x}{4} = \frac{3}{5} - \frac{3}{4}\)

\(\frac{24x - 25x}{20} = \frac{12 - 15}{20}\)

\(\frac{-x}{20} = \frac{-3}{20}\)

-20x = -60

x = \(\frac{-60}{-20}\)

x = 3

1,325.

If N112.00 exchanges for D14.95, calculate the value of D1.00 in naira

A.

0.13

B.

7.49

C.

8.00

D.

13.00

Correct answer is B

D14.95 = N112.00

D1.00 = \(\frac{N112}{D14.95} \times\) D1.00

= 7.49