Year : 
2019
Title : 
Mathematics (Core)
Exam : 
WASSCE/WAEC MAY/JUNE

Paper 1 | Objectives

41 - 50 of 50 Questions

# Question Ans
41.

In the diagram, RT is a tangent to the circle at R, < PQR = 70\(^o\), < QRT = 52\(^o\), < QSR and < PRQ = x. Calculate the variance of 2, 4, 7, 8 and 9

A. 7.2

B. 6.8

C. 3.5

D. 2.6

Detailed Solution


x
2
4
7
8
9
(\(\bar{x} - \bar{x}\))
-4
-2
1
2
4

(\(\bar{x} - \bar{x})^2\)
16
4
1
4
9
_________
\(\sum (x - x)^2\) = 34

\(\bar{x} = \frac{2 + 4 + 7 + 8 + 9}{5} = 6
variance = \(\frac{34}{5}\)
= 6.8

42.

The fourth term of an Arithmetic Progression (A.P) is 37 and the first term is -20. Find the common difference.

A. 3    

B. 57  

C.  19    

D. 17

Detailed Solution

a + 3d = 37
-20 + 3d = 37
3d = 37 + 20 = 57
d = \(\frac{57}{3}\)
= 19
43.

In the diagram, PQ is parallel to RS, < QFG = 105\(^o\) and < FEG = 50\(^o\). Find the value of m.

A. 130\(^o\)

B. 105\(^o\)

C. 75\(^o\)

D. 55\(^o\)

Detailed Solution

50\(^o\) + m = 105\(^o\) (exterior angle of \(\triangle\)
m = 105\(^o\) - 50\(^o\)
m = 55\(^o\)

44.

In the diagram, PQ is parallel to RS, < QFG = 105\(^o\) and < FEG = 50\(^o\). Find the value of n

A. 40\(^o\)

B. 55\(^o\)

C. 75\(^o\)

D. 130\(^o\)

Detailed Solution

E\(G\)R = 50\(^o\) (Alternative angles)
n + 55\(^o\) + 50\(^o\) = 180\(^o\) (Sum of angles on a straight line)
n = 180\(^o\) - 105\(^o\)
n = 75\(^o\)
45.

A box contains 5 red, 6 green and 7 yellow pencils of the same size. What is the probability of picking a green pencil at random?

A. \(\frac{1}{6}\)

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

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

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

Detailed Solution

Pr(green) = \(\frac{6}{5 + 6 + 7}\)
= \(\frac{6}{18}\)
= \(\frac{1}{3}\)
46.

The pie chart represents fruits on display in a grocery shop. If there are 60 oranges on display, how many apples are there?

A. 90

B. 80

C. 70

D. 40

Detailed Solution

No of fruits = x
\(\frac{80}{360}\) x \(x\) = 60
x = \(\frac{60 \times 360}{80}\) x 270
= 90

The following are scores obtained by some students in a test.

47.

Find the mode of the distribution

A. 18

B. 14

C. 13  

D. 8

C

48.

Find the median score

A. 14.5

B. 14.0

C. 13.5

D. 13.0

Detailed Solution

\(\frac{13 + 14}{2}\) = 13.5
49.

How many students scored above the mean score?

A. 10

B. 9

C. 8

D. 7

Detailed Solution

Mean = 13.4
No above mean is 7
50.

Evaluate: \(\frac{0.42 + 2.5}{0.5 \times 2.95}\), leaving the answer in the standard form.

A. 1.639 x 10\(^2\)

B. 1.639 x 10\(^1\)

C. 1.639 x 10\(^{-1}\)

D. 1.639 x 10\(^{-2}\)

Detailed Solution

\(\frac{0.42 \div 2.5}{0.5 \times 2.05} = \frac{0.168}{1.025}\)
= 1.639 x 10\(^{-1}\)
41.

In the diagram, RT is a tangent to the circle at R, < PQR = 70\(^o\), < QRT = 52\(^o\), < QSR and < PRQ = x. Calculate the variance of 2, 4, 7, 8 and 9

A. 7.2

B. 6.8

C. 3.5

D. 2.6

Detailed Solution


x
2
4
7
8
9
(\(\bar{x} - \bar{x}\))
-4
-2
1
2
4

(\(\bar{x} - \bar{x})^2\)
16
4
1
4
9
_________
\(\sum (x - x)^2\) = 34

\(\bar{x} = \frac{2 + 4 + 7 + 8 + 9}{5} = 6
variance = \(\frac{34}{5}\)
= 6.8

42.

The fourth term of an Arithmetic Progression (A.P) is 37 and the first term is -20. Find the common difference.

A. 3    

B. 57  

C.  19    

D. 17

Detailed Solution

a + 3d = 37
-20 + 3d = 37
3d = 37 + 20 = 57
d = \(\frac{57}{3}\)
= 19
43.

In the diagram, PQ is parallel to RS, < QFG = 105\(^o\) and < FEG = 50\(^o\). Find the value of m.

A. 130\(^o\)

B. 105\(^o\)

C. 75\(^o\)

D. 55\(^o\)

Detailed Solution

50\(^o\) + m = 105\(^o\) (exterior angle of \(\triangle\)
m = 105\(^o\) - 50\(^o\)
m = 55\(^o\)

44.

In the diagram, PQ is parallel to RS, < QFG = 105\(^o\) and < FEG = 50\(^o\). Find the value of n

A. 40\(^o\)

B. 55\(^o\)

C. 75\(^o\)

D. 130\(^o\)

Detailed Solution

E\(G\)R = 50\(^o\) (Alternative angles)
n + 55\(^o\) + 50\(^o\) = 180\(^o\) (Sum of angles on a straight line)
n = 180\(^o\) - 105\(^o\)
n = 75\(^o\)
45.

A box contains 5 red, 6 green and 7 yellow pencils of the same size. What is the probability of picking a green pencil at random?

A. \(\frac{1}{6}\)

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

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

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

Detailed Solution

Pr(green) = \(\frac{6}{5 + 6 + 7}\)
= \(\frac{6}{18}\)
= \(\frac{1}{3}\)
46.

The pie chart represents fruits on display in a grocery shop. If there are 60 oranges on display, how many apples are there?

A. 90

B. 80

C. 70

D. 40

Detailed Solution

No of fruits = x
\(\frac{80}{360}\) x \(x\) = 60
x = \(\frac{60 \times 360}{80}\) x 270
= 90

The following are scores obtained by some students in a test.

47.

Find the mode of the distribution

A. 18

B. 14

C. 13  

D. 8

C

48.

Find the median score

A. 14.5

B. 14.0

C. 13.5

D. 13.0

Detailed Solution

\(\frac{13 + 14}{2}\) = 13.5
49.

How many students scored above the mean score?

A. 10

B. 9

C. 8

D. 7

Detailed Solution

Mean = 13.4
No above mean is 7
50.

Evaluate: \(\frac{0.42 + 2.5}{0.5 \times 2.95}\), leaving the answer in the standard form.

A. 1.639 x 10\(^2\)

B. 1.639 x 10\(^1\)

C. 1.639 x 10\(^{-1}\)

D. 1.639 x 10\(^{-2}\)

Detailed Solution

\(\frac{0.42 \div 2.5}{0.5 \times 2.05} = \frac{0.168}{1.025}\)
= 1.639 x 10\(^{-1}\)