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.

756.

An object is 6m away from the base of a mast. If the angle of depression of the object from the top of the mast is 50o, find, correct to 2 decimal places, the height of the mast.

A.

8.60m

B.

7.83m

C.

7.51m

D.

7.15m

Correct answer is D

In the diagram give, \(\alpha\) 50o(alternative angles)

tan\(\alpha\) = \(\frac{h}{6}\)

h = 6tan\(\alpha\)

= 6tan 50o

= 6 x 1.1918

= 7.1508

= 7.15m (2d.p)

757.

In the diagram MN is a chord of a circle KMN centre O and radius 10cm. If < MON = 140o, find, correct to the nearest cm, the length of the chord MN.

A.

19cm

B.

18cm

C.

17cm

D.

12cm

Correct answer is A

From the diagram

sin 70o = \(\frac{x}{10}\)

x = 10sin 70o

= 9.3969

Hence, length of chord MN = 2x

= 2 x 9.3969

= 18.7938

= 19cm (nearest cm)

758.

Halima is n years old. Her brother's age is 5 years more than half of her age. How old is her brother?

A.

\(\frac{n}{2} + \frac{5}{2}\)

B.

\(\frac{n}{2}\) - 5

C.

5 - \(\frac{n}{2}\)

D.

\(\frac{n}{2}\) + 5

Correct answer is D

Halima's age = n years old

Her brother's age = \(\frac{n}{2}\) + 5

759.

The ratio of the exterior angle to the interior angle of a regular polygon is 1:11. How many sides has the polygon?

A.

30

B.

24

C.

18

D.

12

Correct answer is B

Let a represent an interior angle; e represent an exterior angle. A section of the polygon is down in the diagram.

\(\frac{e}{a}\) = \(\frac{l}{11}\) given

a = 11e

a + e = 180o(angles on a straight line)

11e + e = 180o

12e = 180o

e = \(\frac{180^o}{12}\)

= 15o

Hence, number of sides

= \(\frac{360^o}{\tect{size of one exterior angle}\)

= \(\frac{360^o}{14^o}\)

= 24

760.

Find the lower quartile of the distribution illustrated by the cumulative frequency curve

A.

17.5

B.

19.0

C.

27.5

D.

28.0

Correct answer is B

Lower quartile,

Q1 = \(\frac{1}{4}\)Nth term

= \(\frac{1}{4}\) x 600th term

= 150th term

= 15.5 + 3 + 0.5

= 19