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.

1,171.

A chord, 7cm long, is drawn in a circle with radius 3.7cm. Calculate the distance of the chord from the centre of the circle

A.

0.7cm

B.

1.2cm

C.

2.0cm

D.

2.5cm

Correct answer is B

let the chord be AB = 7cm

radius OA = 3.7cm distance of the = OM using Pythagoras theorem

OA2 = AM2 + OM2

3.72 = 3.52 + OM2

13.69 = 12.25 + OM2

13.69 - 12.25 = OM2

1.44 = OM2

OM = \(\sqrt{1.44}\)

OM = 1.2cm

distance of chord = 1.2cm

1,172.

The area of a sector a circle with diameter 12cm is 66cm2. If the sector is folded to form a cone, calculate the radius of the base of the cone [Take \(\pi = \frac{22}{7}\)]

A.

3.0cm

B.

3.5cm

C.

7.0cm

D.

7.5cm

Correct answer is B

diameter = 12cm

radius = \(\frac{12}{2}\)cm = 6cm

area of sector = 66cm2

area of sector = area of cone

66 = \(\pi rl\)

66 = \(\frac{22}{7} \times r \times 6\)

divide both sides by 6

11 = \(\frac{22}{7}r\)

22r = 11 x 7

r = \(\frac{77}{22}\)

= 3.5cm

1,173.

\(\begin{array}{c|c}height & 2 & 3 & 4 & 5 & 6 \\ \hline frequency & 2 & 4 & 5 & 3 & 1
\end{array}\)
The table shows the distribution of the height of plants in a nursery. Calculate the mean height of the plants.

A.

3.8

B.

3.0

C.

2.8

D.

2.3

Correct answer is A

\(\begin{array}{c|c} height(x) & frequency(f) & fx \\ \hline 2 & 2 & 4\\ 3 & 4 & 12\\ 4 & 5 & 20 \\ 5 & 3 & 15\\ 6 & 1 & 6\end{array}\)

mean\(\bar{x} = \frac{\sum fx}{\sum f}\)

= \(\frac{57}{15}\)

= 3.8

1,174.

If (x - a) is a factor pf bx - ax + x2, find the other factor.

A.

(x + b)

B.

(x - b)

C.

(a + b)

D.

(a - b)

Correct answer is A

No explanation has been provided for this answer.

1,175.

Find the gradient of the line joining the points (2, -3) and 2, 5)

A.

9

B.

1

C.

2

D.

undefined

Correct answer is D

(2, -3)(2, 5)

gradient = \(\frac{y_ = y_1}{x_2 = x_1} = \frac{5 - (-3)}{2 - 2}\)

= \(\frac{5 + 3}{0}\)

= \(\frac{8}{0}\)

= undefined