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.

2,926.

A chord of length 30cm is 8cm away from the center of the circle. What is the radius of the circle? Take \(\pi =\frac{22}{7}\)

A.

16cm

B.

17cm

C.

18cm

D.

20cm

Correct answer is B

From the diagram
\(r^2 = B^2 + 15^2\\
= 64 + 225\\
r = \sqrt{289} = 17cm\)

2,927.

The height of a right circular cone is 4cm. The radius of its base is 3cm. Find the curved surface area

A.

\(9\pi cm^2\)

B.

\(15\pi cm^2\)

C.

\(16\pi cm^2\)

D.

\(20\pi cm^2\)

Correct answer is B

Curved surface area or a cone \(=\pi rl\)
from the information \(l^2 = 4^2 + 3^2 = 16+9\\
l = \sqrt{25} = 5; ∴ C.S.A\hspace{1mm} = \frac{22}{7}\times 3 \times 5\\
Since \frac{22}{7}=\pi ∴ C.S.A\hspace{1mm} =\hspace{1mm}15\pi\)

2,928.

A right pyramid is on a square base of side 4cm. The slanting side of the pyramid is \(2\sqrt{3}\) cm. Calculate the volume of the pyramid

A.

\(5\frac{1}{3}cm^3\)

B.

\(10\frac{2}{3}cm^3\)

C.

\(16cm^3\)

D.

\(32cm^3\)

Correct answer is B

No explanation has been provided for this answer.

2,929.

In the diagram O is the center of the circle. Reflex angle XOY = 210° and the length of the minor arc is 5.5m. Find, correct to the nearest meter, the length of the major arc.

A.

8m

B.

9m

C.

10m

D.

13m

Correct answer is A

Given, Length of minor arc = 5.5m

Angle subtended by minor arc = 360° - 210° = 150°

\(\therefore 5.5 = \frac{150}{360} \times 2 \times \frac{22}{7} \times r \)

\(\frac{55r}{21} = 5.5\)

\(r = \frac{5.5 \times 21}{55}\)

r = 2.1m

Length of major arc = \(\frac{210}{360} \times 2 \times \frac{22}{7} \times 2.1\)

= \(7.7m \approxeq 8m\) (to the nearest metre)

2,930.

In the diagram, PQ is the diameter of the circle and ∠PRS = 58°. Find ∠STQ.

A.

29o

B.

32o

C.

42o

D.

53o

Correct answer is B

In \(\Delta\) PRQ, < SRQ = 90° - 58°

< SRQ = < QTS = x (angles in the segment)

\(\therefore\) x = 32°