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.

146.

The mean of a set of 10 numbers is 56. If the mean of the first nine numbers is 55, find the 10th number.

A.

75

B.

65

C.

55

D.

45

Correct answer is B

10th number must be over 56 (as it increases the average)

55 x 9 = 495 = sum of first 9 numbers

56 x 10 = 560 = sum of all 10 numbers

560 - 495 = 65 = 10th number

147.

Mrs Gabriel is pregnant. The probability that she will give birth to a girl is 1/2 and with  blue eyes is 1/4. What is the probability that she will give birth to a girl with blue eyes? 

A.

1

B.

\(\frac{3}{4}\)

C.

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

D.

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

Correct answer is C

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

Blue eyes = \(\frac{1}{4}\)

probability that she will give birth to a girl with blue eyes: \(\frac{1}{2}\) x \(\frac{1}{4}\)

= \(\frac{1}{8}\)

148.

Find ∠SON

A.

36º

B.

42º

C.

54º

D.

72º

Correct answer is A

The sum of angles in a triangle = 180º

(180 - 108)º = 72º

Isosceles triangle has both two equal sides and two equal angles.

 ∠OSN =  ∠SON = \(\frac{72}{2}\)

= 36º

149.

In the diagram, MNR is a tangent to the circle centre O at N and ∠NOS = 108°. Find ∠OSN

A.

72°

B.

32°

C.

36°

D.

18°

Correct answer is C

The sum of angles in a triangle = 180º

(180 - 108)º = 72º

Isosceles triangle has both two equal sides and two equal angles.

 ∠OSN =  ∠SON = \(\frac{72}{2}\)

= 36º

150.

Given that sin (5x-28)° = cos (3x-50)", 0°≤ x ≤ 90°, find the value of x.

A.

39

B.

32

C.

21

D.

14

Correct answer is B

using the trial method by inserting each option in the equation.

Inserting 21º: sin([5 x 21] - 28) = cos([3 x 21] - 50)

sin(105 - 28) = cos (63 - 50)

sin 77º = cos 13º 

where:

sin 77º = 0.9744

cos 13º =  0.9744