Loading [MathJax]/jax/output/HTML-CSS/jax.js

JAMB Mathematics Past Questions & Answers - Page 34

166.

The acres for rice, pineapple, cassava, cocoa and palm oil in a certain district are given respectively as 2, 5, 3, 11 and 9. What is the angle of the sector of cassava in a pie chart? 

A.

180o

B.

36o

C.

60o

D.

108o

Correct answer is B

Total number of acres = 2 + 5 + 3 + 11 + 9 = 30

The angle of acres = 2 + 5 + 3 + 11 + 9 = 30

The angle of the sector for cassava in a pie chart = 330×360o=36o 

167.

A cylindrical tank has a capacity of 3080m3. What is the depth of the tank if the diameter of its base is 14m?

A.

25m

B.

23m

C.

22m

D.

20m

Correct answer is D

V = 2080cm3, h = ? 

r = 7cm

V = Vπr2h

h = Vπr2=3080227×49 

308054 = 20cm

169.

The chord ST of a circle is equal to the radius r of the circle. Find the length of arc ST

A.

πr3

B.

πr2

C.

πr12

D.

πr6

Correct answer is A

r2r Sin θ = 12 

θ = sin1 (12) = 30o = 60o 

Length of arc (minor)

ST = θ360 x 2πr 

60360×2π×r=π3 

170.

A binary operation x is defined by a x b = ab. If a x 2 = 2 - a, find the possible values of a?

A.

1, -2

B.

2, -1

C.

2, -2

D.

1, -1

Correct answer is A

a = b = a2

a + 2 = a2.....(i)

a + 2 = 2 - a..............(ii) 

a2 = 2 - a 

a2+ a - 2 = a2 + a - 2 = 0

= (a + 2)(a - 1) = 0

a = 1 or - 2