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.

171.

Evaluate 23 x 54 (mod 7)

A.

2

B.

3

C.

5

D.

6

Correct answer is B

23 x 54 = 1242

In mod 7; 

1242 ÷ 7 = 177 R 3 

Hence; 1242 ≡ 3

172.

If 24 + 96 - 600 = y6, find the value of y

A.

4

B.

2

C.

-2

D.

-4

Correct answer is D

24 + 96 - 600 = y6

convert all to basic surds

24 = 26

96 = 46

600 = -106

26 + 46 - 106 = -46

value of y = -4

173.

Given that A and B are sets such that n(A) = 8, n(B)=12 and n(AnB) =3, find n(AuB).

A.

15

B.

17

C.

20

D.

23

Correct answer is B

n(AuB) = n(A) + n(B) -  n(AnB)

n(AuB) = 8 + 12 - 3

= 17 

174.

Change 432\(_{five}\)  to a number in base three.

A.

10100\(_{three}\)

B.

11100\(_{three}\)

C.

11101\(_{three}\)

D.

10110\(_{three}\)

Correct answer is B

Convert from base 5 to base 10

432\(_{five}\) =  (4 x 5\(^2\)) + (3 x 5\(^1\)) + (2 x 5\(^0\))

= (4 x 25) + (3 x 5) + (2 x 1)

= 100 + 15 + 2

= 117\(_{ten}\)

Then convert from base 10 to base 3

3 117
3 39 r 0
3 13 r 0
3 4 r 1
3 1 r 1
  0 r 1

Selecting the remainders from bottom to top:

117\(_{ten}\) = 11100\(_{three}\)

Hence; 432\(_{five}\) =  11100\(_{three}\)

175.

Evaluate, correct to four significant figures, (573.06 x 184.25).

A.

105600.00

B.

105622.00

C.

105500.00

D.

105632.00

Correct answer is A

573.06 x 184.25 = 105,586.305

1,05600.00 to four significant figure

What are the Rules for significant figures?

Significant Figures

  • All non-zero numbers ARE significant.
  • Zeros between two non-zero digits ARE significant. 
  • Leading zeros are NOT significant.
  • Trailing zeros to the right of the decimal ARE significant.
  • Trailing zeros in a whole number with the decimal shown ARE significant.