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.

571.

Simplify the expression \(\frac{a^2 b^4 - b^2 a^4}{ab(a + b)}\)

A.

\(a^2 - b^2\)

B.

\(b^2 - a^2\)

C.

\(a^2b - ab^2\)

D.

\(ab^2 - a^2b\)

Correct answer is D

\(\frac{a^2 b^4 - b^2 a^4}{ab(a + b)}\) = \(\frac{a^2 b^24(b^2 - a^2}{ab(a + b)}\)

= \(\frac{ab [(b - a) (b + a)]}{a + b}\)

= ab(b - a)

= \(ab^2 - a^2b\)

572.

Three exterior angles of a polygon are 30\(^o\), 40\(^o\) and 60\(^o\). If the remaining exterior angles are 46\(^o\) each, name the polygon.

A.

decagon

B.

nonagon

C.

octagon

D.

hexagon

Correct answer is C

Sum of all exterior angles is 360\(^o\)

360\(^o\) (30\(^o\) - 40\(^o\))

360 - (130\(^o\))

230\(^o\)

remaining is 46\(^o\) = \(\frac{230}{46}\) = 5

5 + 3 = 8 sides; Octagon

573.

Simplify; \(\sqrt{2}(\sqrt{6} + 2\sqrt{2}) - 2\sqrt{3}\)

A.

4

B.

\(\sqrt{3} + 4\)

C.

4 \(\sqrt{2}\)

D.

4\(\sqrt{3} + 4\)

Correct answer is A

\(\sqrt{2}(\sqrt{6} + 2\sqrt{2}) - 2\sqrt{3}\)

\(\sqrt{12}\) + 2 x 2 - 2\(\sqrt{3}\)

2 \(\sqrt{3}\) - 2 \(\sqrt{3}\) + 4

= 4

574.

In what number base was the addition 1 + nn = 100, where n > 0, done?

A.

n - 1

B.

n + 1

C.

n

D.

n + 2

Correct answer is C

No explanation has been provided for this answer.

575.

The average age of a group of 25 girls is 10year. If one girl, aged 12 years and 4 months joins the group, find the new average age of the group

A.

10.1 years

B.

9.3 years

C.

8.7 years

D.

8 . 3 years

Correct answer is A

x = 10 ; 10 = \(\frac{x}{25}\)

x = 250

x = \(\frac{250 + 12.4}{26}\)

x = 10.09

x = 10.1 years