Year : 
2013
Title : 
Mathematics (Core)
Exam : 
WASSCE/WAEC MAY/JUNE

Paper 1 | Objectives

31 - 40 of 48 Questions

# Question Ans
31.

The slant height of a cone is 5cm and the radius of its base is 3cm. Find, correct to the nearest whole number, the volume of the cone. ( Take \(\pi = \frac{22}{7}\))

A. 48cm3

B. 47cm3

C. 38cm3

D. 12cm3

Detailed Solution

Volume of a cone = \(\frac{1}{3} \pi r^2h\)

h2 = 52 = 32

= 25 - 9 = 16

h = \(\sqrt{16}\)

h = 4cm

v = \(\frac{1}{3} \times \frac{22}{7} \times 3^2 \times 4\)

\(\frac{1}{3} \times \frac{22}{7} \times 9 \times 4\)

= \(\frac{22 \times 3 \times 4}{7}\)

= 37.7cm3

= 38cm3
32.

The distance between two towns is 50km. It is represented on a map by 5cm. Find the scale used

A. 1: 1,000,000

B. 1: 500,000

C. 1: 100,000

D. 1: 10,000

Detailed Solution

1km = 100,000cm

on the map 1 cm represent every 10 km which is equal to (10 x 100,000cm)

= 1,000,000cm

the scale is 1:1,000,000
33.

Given that (x + 2)(x2 - 3x + 2) + 2(x + 2)(x - 1) = (x + 2) M, find M

A. (x + 2)2

B. x(x + 2)

C. xv + 2

D. x2 - x

Detailed Solution

(x = 2)(x2 - 3x + 2) + 2(x + 2)(x - 1) = (x + 2)m

(m + 2)[(x2 - 3x + 2) + 2(x - 1)] = (x + 2)M

divide both side by (x + 2)

(x2 - 3x + 2) + 2(x - 1) = M

x2 - 3x + 2 + 2x - 2 = M

x2 - 3x + 2 + 2x - 2 = M

x2 - 3x + 2x = M

x2 - x = M

M = x2 - x
34.

An open cone with base radius 28cm and perpendicular height 96cm was stretched to form sector of a circle. calculate the arc of the sector (Take \(\pi = \frac{22}{7}\))

A. 8800cm2

B. 8448cm2

C. 4400cm2

D. 4224cm2

Detailed Solution

L2 = 962 + 282

= 9216 + 784

= 10000

L = \(\sqrt{10000}\)

= 100cm

curved surface area = \(\pi r l\)

= \(\frac{22}{7} \times 28 \times 100\)

= 8800cm2

area of cone = area of sector

area of sector = 8800cm2
35.

In the diagram, PRST is a square. If |PQ| = 24cm. |QR| = 10cm and < PQR = 90o, find the perimeter of the polygon PQRST.

A. 112cm

B. 98cm

C. 86cm

D. 84cm

A

36.

In the diagram, the height of a flagpole |TF| and the length of its shadow |FL| re in the ratio 6:8. Using k as a constant of proportionality, find the shortest distance between T and L

A. 7K units

B. 10K units

C. 12K units

D. 14k units

Detailed Solution

by Pythagoras x2 = 62 + 82

36 + 64 = 100

x = \(\sqrt{100}\)

x = 10
37.

In the diagrams, |XZ| = |MN|, |ZY| = |MO| and |XY| = |NO|. Which of the following statements is true?

A. \(\bigtriangleup\) ZYX = \(\bigtriangleup\) OMN

B. \(\bigtriangleup\) YZX = \(\bigtriangleup\) NOM

C. \(\bigtriangleup\) ZXY= \(\bigtriangleup\) MON

D. \(\bigtriangleup\) XYZ= \(\bigtriangleup\) NOM

D

38.

In the diagram, PQRS is a rhombus and < PSQ = 35o. Calculate the size of < PRO

A. 65o

B. 55o

C. 45o

D. 35o

Detailed Solution

The diagonals of rhombus bisects its angles
39.

Find the value of m in the diagram

A. 34o

B. 27o

C. 23o

D. 17o

Detailed Solution

\(\bigtriangleup\) ABC, A + 153 = 180 (angles on straight line)

< A = 180 - 153 = 27

< B = 2m(vertically opposite angles)

< C = 7m (corresponding ngles)

< A + < B + < C = 180 (sum of int. angles of \(\bigtriangleup\))

i.e. 27 + 2m + 7m = 180o

9m = 180 - 27

9m = 153

m = \(\frac{153}{9}\)

= 17
40.

In the diagram, O is the centre of the circle. OM||XZ and < ZOM = 25o

A. 50o

B. 55o

C. 60o

D. 65o

C

31.

The slant height of a cone is 5cm and the radius of its base is 3cm. Find, correct to the nearest whole number, the volume of the cone. ( Take \(\pi = \frac{22}{7}\))

A. 48cm3

B. 47cm3

C. 38cm3

D. 12cm3

Detailed Solution

Volume of a cone = \(\frac{1}{3} \pi r^2h\)

h2 = 52 = 32

= 25 - 9 = 16

h = \(\sqrt{16}\)

h = 4cm

v = \(\frac{1}{3} \times \frac{22}{7} \times 3^2 \times 4\)

\(\frac{1}{3} \times \frac{22}{7} \times 9 \times 4\)

= \(\frac{22 \times 3 \times 4}{7}\)

= 37.7cm3

= 38cm3
32.

The distance between two towns is 50km. It is represented on a map by 5cm. Find the scale used

A. 1: 1,000,000

B. 1: 500,000

C. 1: 100,000

D. 1: 10,000

Detailed Solution

1km = 100,000cm

on the map 1 cm represent every 10 km which is equal to (10 x 100,000cm)

= 1,000,000cm

the scale is 1:1,000,000
33.

Given that (x + 2)(x2 - 3x + 2) + 2(x + 2)(x - 1) = (x + 2) M, find M

A. (x + 2)2

B. x(x + 2)

C. xv + 2

D. x2 - x

Detailed Solution

(x = 2)(x2 - 3x + 2) + 2(x + 2)(x - 1) = (x + 2)m

(m + 2)[(x2 - 3x + 2) + 2(x - 1)] = (x + 2)M

divide both side by (x + 2)

(x2 - 3x + 2) + 2(x - 1) = M

x2 - 3x + 2 + 2x - 2 = M

x2 - 3x + 2 + 2x - 2 = M

x2 - 3x + 2x = M

x2 - x = M

M = x2 - x
34.

An open cone with base radius 28cm and perpendicular height 96cm was stretched to form sector of a circle. calculate the arc of the sector (Take \(\pi = \frac{22}{7}\))

A. 8800cm2

B. 8448cm2

C. 4400cm2

D. 4224cm2

Detailed Solution

L2 = 962 + 282

= 9216 + 784

= 10000

L = \(\sqrt{10000}\)

= 100cm

curved surface area = \(\pi r l\)

= \(\frac{22}{7} \times 28 \times 100\)

= 8800cm2

area of cone = area of sector

area of sector = 8800cm2
35.

In the diagram, PRST is a square. If |PQ| = 24cm. |QR| = 10cm and < PQR = 90o, find the perimeter of the polygon PQRST.

A. 112cm

B. 98cm

C. 86cm

D. 84cm

A

36.

In the diagram, the height of a flagpole |TF| and the length of its shadow |FL| re in the ratio 6:8. Using k as a constant of proportionality, find the shortest distance between T and L

A. 7K units

B. 10K units

C. 12K units

D. 14k units

Detailed Solution

by Pythagoras x2 = 62 + 82

36 + 64 = 100

x = \(\sqrt{100}\)

x = 10
37.

In the diagrams, |XZ| = |MN|, |ZY| = |MO| and |XY| = |NO|. Which of the following statements is true?

A. \(\bigtriangleup\) ZYX = \(\bigtriangleup\) OMN

B. \(\bigtriangleup\) YZX = \(\bigtriangleup\) NOM

C. \(\bigtriangleup\) ZXY= \(\bigtriangleup\) MON

D. \(\bigtriangleup\) XYZ= \(\bigtriangleup\) NOM

D

38.

In the diagram, PQRS is a rhombus and < PSQ = 35o. Calculate the size of < PRO

A. 65o

B. 55o

C. 45o

D. 35o

Detailed Solution

The diagonals of rhombus bisects its angles
39.

Find the value of m in the diagram

A. 34o

B. 27o

C. 23o

D. 17o

Detailed Solution

\(\bigtriangleup\) ABC, A + 153 = 180 (angles on straight line)

< A = 180 - 153 = 27

< B = 2m(vertically opposite angles)

< C = 7m (corresponding ngles)

< A + < B + < C = 180 (sum of int. angles of \(\bigtriangleup\))

i.e. 27 + 2m + 7m = 180o

9m = 180 - 27

9m = 153

m = \(\frac{153}{9}\)

= 17
40.

In the diagram, O is the centre of the circle. OM||XZ and < ZOM = 25o

A. 50o

B. 55o

C. 60o

D. 65o

C