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.

376.

Make b the subject of the relation lb = \(\frac{1}{2}\) (a + b)h

A.

\(\frac{ah}{2l - h}\)

B.

\(\frac{2l - h}{al}\)

C.

\(\frac{al}{2l - h}\)

D.

\(\frac{al}{2 - h}\)

Correct answer is A

lb = \(\frac{1}{2} (a + b)h

2lb = ah + bh

2lb - bh = ah

\(\frac{b(2l - h)}{2l - h} = \frac{ah}{2l - h}\)

b = \(\frac{ah}{2l - h}\)

377.

An arc subtends an angle of 72\(^o\) at the centre of a circle. Find the length of the arc if the radius of the circle is 3.5 cm. [Take \(\pi = \frac{22}{7}\)]

A.

6.6 cm

B.

8.8 cm

C.

4.4 cm

D.

2.2 cm

Correct answer is C

Length = \(\frac{\theta}{360}\) x 2\(\pi\)r

= \(\frac{72}{360} \times 2 \frac{22}{7} \times \frac{0.5}{3.5}\)

= 4.4

378.

If log\(_x\) 2 = 0.3, evaluate log\(_x\) 8.

A.

2.4

B.

1.2

C.

0.9

D.

0.6

Correct answer is C

log\(_x\)2 = 0.3

log\(_x\)8 =  log\(_x\)2\(^3\) = 3 log\(_x\)2

= 3 x 0.3 

= 0.9

379.

In XYZ, |YZ| = 32cm, < YXZ 53\(^o\) and XZY = 90\(^o\). Find, correct to the nearest centimetre, |XZ|

A.

31 cm

B.

25 cm

C.

20 cm

D.

13 cm

Correct answer is B

Tan 52\(^o\) = \(\frac{32}{\text{|XZ|}}\)

|XZ| = \(\frac{32}{Tan 52^o}\)

= 25cm

380.

If 2\(^{a}\) = \(\sqrt{64}\) and \(\frac{b}{a}\) = 3, evaluate a\(^2 + b^{2}\) 

A.

250

B.

160

C.

90

D.

48

Correct answer is C

2\(^a\) = \(\sqrt{64}\)

2\(^a\) = 8

2\(^a\) = 2\(^3\)

a = 3

b = 3\(^a\)

b = 3 x 3 = 9

a\(^2\) + b\(^2\) = 3\(^2\) + 9\(^2\) 

= 9 + 81 = 90