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.

651.

Approximate 0.9875 to 1 decimal place.

A.

1.1

B.

1.0

C.

0.9

D.

0.10

Correct answer is B

9 is on one decimal place, the next number to it is 8 which will be rounded up to 1 because it is greater than 5 and then added to 9 to give 10, 10 cannot be written, it will then be rounded up to 1 and added to 0. So the answer is 1.0

652.

Calculate the area of an equilateral triangle of side 8cm

A.

8√3

B.

16

C.

4√3

D.

16√3

Correct answer is D

An equilateral triangle has all sides equal and all angles equal as 600

  Area = \(\frac{1}{2}\) absinθ

  Area = \(\frac{1}{2}\) x 8 x 8 x sin60

  = \(\frac{1}{2}\) x 64 x \(\sqrt{\frac{3}{2}}\)

  = 16√3 cm\(^2\)

653.

Which one of the following gives the members of the set A1 n B n C?

A.

Φ

B.

{s}

C.

{t, u}

D.

{y, z}

Correct answer is A

A1 = Elements in the universal set but not in A = {s, w, x, y, z} B = {r, s. t, u} C = {t, u, v, w, x} A1 n B n C = elements common to the three sets = none = empty set = Φ

654.

A box contains two red balls and four blue balls. A ball is drawn at random from the box and then replaced before a second ball is drawn. Find the probability of drawing two red balls.

A.

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

B.

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

C.

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

D.

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

Correct answer is D

Total number of balls = 2 + 4 = 6

  P(of picking a red ball) = \(\frac{2}{6}\) = \(\frac{1}{3}\)

  P(of picking a blue ball) = \(\frac{4}{6}\) = \(\frac{2}{3}\)

  With replacement,

  P( picking two red balls) = \(\frac{1}{3}\) × \(\frac{1}{3}\) = \(\frac{1}{9}\)

655.

if y = 23\(_{five}\) + 101\(_{three}\) find y leaving your answer in base two

A.

1110

B.

10111

C.

11101

D.

111100

Correct answer is B

First we convert the numbers to base ten

  23\(_{five}\)= 2 x 51 + 3 x 50

  = 10 + 3 = 13

  101\(_{five}\) = (1 x 32) + (0 x 31) + (1 x 30)

  = 9 + 0 + 1 = 10

  So, y = 13 + 10 = 23

  To convert 23 to base 2 (as in the diagram above)

Y = 23

  = 10111\(_{five}\)

Answer is B