Year : 
2020
Title : 
Mathematics (Core)
Exam : 
WASSCE/WAEC MAY/JUNE

Paper 1 | Objectives

31 - 40 of 50 Questions

# Question Ans
31.

Open Photo In the diagram, \(\overline{PS}\)/\(\overline{SR}\), \(\overline{PS}\)/\(\overline{TR}\), \(\overline{QS}\)/\(\overline{UR}\), \(\overline{PS}\) = 15cm, \(\overline{SR}\) = 8cm, \(\overline{PS}\) = 10cm and area of \(\triangle\) SUR = 24cm\(^2\). Calculate the area of PTRS.

A. 40 cm\(^2\)

B. 48 cm\(^2\)

C. 80 cm\(^2\)

D. 120 cm\(^2\)

Detailed Solution

Area PTRS = 10cm x 8cm
= 80cm
32.

Open Photo In the diagram, PQR is a circle with centre O. If < OPQ = 48\(^o\), find the value of m

A. 96\(^o\)

B. 90\(^o\)

C. 68\(^o\)

D. 42\(^o\)

Detailed Solution

< O\(Q\)P = 48\(^o\) (base angles of isoceles \(\triangle\))
m = 48\(^o\) + 48\(^o\) = 96\(^o\) (exterior angle of a \(\triangle\))
33.

Open PhotoThe pie chart shows the population of men, women, and children in a city. If the population of the city is 1,800,000, how many men are in the city?

A. 845,000

B. 600,000

C. 355,000

D. 250,000

Detailed Solution

Angle of Men = 360\(^o\) - (120 + 169)
= 360\(^o\) - 289\(^o\) = 71\(^o\)
No. of men \(\frac{71}{360}\) x 1800,000
= 355,000
34.

The mean of the numbers 15, 21, 17, 26, 18, and 29 is 21. Calculate the standard deviation

A. 9

B. 6

C. 5

Detailed Solution

x
15
21
17
26
18
29
-6
0
-4
5
-3
-8
36
0
16
25
9
64

Standard deviation = \(\sqrt{\frac{ \sum (x - \overline{x})^2}{n} }\)
= \(\frac{150}{6}\)
= \(\sqrt{25}\)
= 5
35.

Open Photo In the diagram, O is the centre of the circle. SOQ is the diameter and < SRP = 37\(^o\). Find < PSQ.

A. 127\(^o\)

B. 65\(^o\)

C. 53\(^o\)

D. 37\(^o\)

Detailed Solution


< PSQ = 180\(^o\) - (37\(^o\) + 90\(^o\))
= 180\(^o\) - 127\(^o\) = 53\(^o\)
36.

Find the sum of the interior angle of a pentagon.

A. 340\(^o\)

B. 350\(^o\)

C. 540\(^o\)

D. 550\(^o\)

Detailed Solution

Sum = (5 - ) 180\(^o\)
= (5 - 2) 180\(^o\) = 3 x 180\(^o\)
= 540\(^o\)
37.

The diameter of a sphere is 12 cm. Calculate, correct of the nearest cm\(^3\), the volume of the sphere, [Take \(\pi = \frac{22}{7}\)]

A. 903 cm\(^3\)

B. 904 cm\(^3\)

C. 905 cm\(^3\)

D. 906 cm\(^3\)

38.

A box contains 12 identical balls of which 5 are red, 4 blue, and the rest are green. If a ball is selected at random from the box, what is the probability that it is green?

A. \(\frac{3}{4}\)

B. \(\frac{1}{2}\)

C. \(\frac{1}{3}\)

D. \(\frac{1}{4}\)

Detailed Solution

No. of red = 5
No. of blue = 4
No. of green = 3
Total = 12
Pr(Green) = \(\frac{3}{12} = \frac{1}{4}\)
39.

A box contains 12 identical balls of which 5 are red, 4 blue, and the rest are green. If two balls are selected at random one after the other with replacement, what is the probability that both are red?

A. \(\frac{25}{144}\)

B. \(\frac{5}{33}\)

C. \(\frac{5}{6}\)

D. \(\frac{103}{132}\)

Detailed Solution

Pr(RR) = \(\frac{5}{12}\) = \(\frac{5}{12} \times \frac{5}{12} = \frac{25}{144}\)
40.

Open PhotoIn the diagram PQ is a straight line. If m = \(\frac{1}{2}\) (x + y + z), find value of m.

A. 45\(^o\)

B. 60\(^o\)

C. 90\(^o\)

D. 100\(^o\)

Detailed Solution

x + y + m + 2 = 180\(^o\)
\(\frac{x + y + 2}{2} + \frac{m}{2}\) = 90\(^o\)
m + \(\frac{m}{2} = 90^o\)
3m = 2 x 90\(^o\)
\(\frac{3m}{3} = \frac{180^o}{3}\)
m = 60\(^o\)
31.

Open Photo In the diagram, \(\overline{PS}\)/\(\overline{SR}\), \(\overline{PS}\)/\(\overline{TR}\), \(\overline{QS}\)/\(\overline{UR}\), \(\overline{PS}\) = 15cm, \(\overline{SR}\) = 8cm, \(\overline{PS}\) = 10cm and area of \(\triangle\) SUR = 24cm\(^2\). Calculate the area of PTRS.

A. 40 cm\(^2\)

B. 48 cm\(^2\)

C. 80 cm\(^2\)

D. 120 cm\(^2\)

Detailed Solution

Area PTRS = 10cm x 8cm
= 80cm
32.

Open Photo In the diagram, PQR is a circle with centre O. If < OPQ = 48\(^o\), find the value of m

A. 96\(^o\)

B. 90\(^o\)

C. 68\(^o\)

D. 42\(^o\)

Detailed Solution

< O\(Q\)P = 48\(^o\) (base angles of isoceles \(\triangle\))
m = 48\(^o\) + 48\(^o\) = 96\(^o\) (exterior angle of a \(\triangle\))
33.

Open PhotoThe pie chart shows the population of men, women, and children in a city. If the population of the city is 1,800,000, how many men are in the city?

A. 845,000

B. 600,000

C. 355,000

D. 250,000

Detailed Solution

Angle of Men = 360\(^o\) - (120 + 169)
= 360\(^o\) - 289\(^o\) = 71\(^o\)
No. of men \(\frac{71}{360}\) x 1800,000
= 355,000
34.

The mean of the numbers 15, 21, 17, 26, 18, and 29 is 21. Calculate the standard deviation

A. 9

B. 6

C. 5

Detailed Solution

x
15
21
17
26
18
29
-6
0
-4
5
-3
-8
36
0
16
25
9
64

Standard deviation = \(\sqrt{\frac{ \sum (x - \overline{x})^2}{n} }\)
= \(\frac{150}{6}\)
= \(\sqrt{25}\)
= 5
35.

Open Photo In the diagram, O is the centre of the circle. SOQ is the diameter and < SRP = 37\(^o\). Find < PSQ.

A. 127\(^o\)

B. 65\(^o\)

C. 53\(^o\)

D. 37\(^o\)

Detailed Solution


< PSQ = 180\(^o\) - (37\(^o\) + 90\(^o\))
= 180\(^o\) - 127\(^o\) = 53\(^o\)
36.

Find the sum of the interior angle of a pentagon.

A. 340\(^o\)

B. 350\(^o\)

C. 540\(^o\)

D. 550\(^o\)

Detailed Solution

Sum = (5 - ) 180\(^o\)
= (5 - 2) 180\(^o\) = 3 x 180\(^o\)
= 540\(^o\)
37.

The diameter of a sphere is 12 cm. Calculate, correct of the nearest cm\(^3\), the volume of the sphere, [Take \(\pi = \frac{22}{7}\)]

A. 903 cm\(^3\)

B. 904 cm\(^3\)

C. 905 cm\(^3\)

D. 906 cm\(^3\)

38.

A box contains 12 identical balls of which 5 are red, 4 blue, and the rest are green. If a ball is selected at random from the box, what is the probability that it is green?

A. \(\frac{3}{4}\)

B. \(\frac{1}{2}\)

C. \(\frac{1}{3}\)

D. \(\frac{1}{4}\)

Detailed Solution

No. of red = 5
No. of blue = 4
No. of green = 3
Total = 12
Pr(Green) = \(\frac{3}{12} = \frac{1}{4}\)
39.

A box contains 12 identical balls of which 5 are red, 4 blue, and the rest are green. If two balls are selected at random one after the other with replacement, what is the probability that both are red?

A. \(\frac{25}{144}\)

B. \(\frac{5}{33}\)

C. \(\frac{5}{6}\)

D. \(\frac{103}{132}\)

Detailed Solution

Pr(RR) = \(\frac{5}{12}\) = \(\frac{5}{12} \times \frac{5}{12} = \frac{25}{144}\)
40.

Open PhotoIn the diagram PQ is a straight line. If m = \(\frac{1}{2}\) (x + y + z), find value of m.

A. 45\(^o\)

B. 60\(^o\)

C. 90\(^o\)

D. 100\(^o\)

Detailed Solution

x + y + m + 2 = 180\(^o\)
\(\frac{x + y + 2}{2} + \frac{m}{2}\) = 90\(^o\)
m + \(\frac{m}{2} = 90^o\)
3m = 2 x 90\(^o\)
\(\frac{3m}{3} = \frac{180^o}{3}\)
m = 60\(^o\)