Year : 
2008
Title : 
Mathematics (Core)
Exam : 
WASSCE/WAEC MAY/JUNE

Paper 1 | Objectives

41 - 45 of 45 Questions

# Question Ans
41.

If the perimeter of \(\bigtriangleup\)PQR in thr diagram is 24cm, what is the area of \(\bigtriangleup\)PRS?

A. 19.5cm2

B. 15.0cm2

C. 13.0cm2

D. 9.3cm2

Detailed Solution

Perimeter of \(\bigtriangleup\) PQR = PQ + QR + PR

24cm = 6cm + 8cm = PR

24 = 14 + PR

PR = 24 - 14 = 10cm

Area of \(\bigtriangleup\) PRS = \(\frac{1}{2} \times 10 \times 3cm^3\)

= 15cm3
42.

In the diagram, PX is a tangent to the circle and RST is an equilateral triangle. Calculate < PTS

A. 60o

B. 90o

C. 120o

D. 150o

Detailed Solution

\(\bigtriangleup\) RST is equilateral triangle, hence

< TRS = < RTS = < RSt = 60o

But < PTR = 60o(Angle between a chord and a tangent at the point of contact = Angle in the alt. segment). From the diagram < PTS = < PTR + < RTS

= 60o + 60o = 120o
43.

In the diagram, < QPR = 60o

< PQR = 50o

< QRS = 2xo

< SRP = 3xo

< UQP = yo and RS//TU

calculate y

A. 102o

B. 78o

C. 70o

D. 60o

Detailed Solution

< RQT = < QRS = 2x (Alternate angles). But in \(\bigtriangleup\) PRQ

50 + 60 + (2x + 3x) = 180o(Angles in a triangle)

110 + 5x = 180o

5x = 180o - 110 = 70o

x = \(\frac{70}{5}\) = 14o

Also y + 50 + 2(14) = 180o

y + 50 + 28 = 180o

y = 180 - 78

44.

In the diagram, find the size of the angle marked a°

A. 60o

B. 80o

C. 120o

D. 160o

Detailed Solution

2 x s = 280°(Angle at centre = 2 x < at circum)

S = \(\frac{280^o}{2}\)

= 140°

< O = 360 - 280 = 80°

60 + 80 + 140 + a = 360°

(< in a quad); 280 + a = 360

a = 360 - 280

a = 80°
45.

Every staff in an office owns either a Mercedes and/or a Toyota car. 20 own Mercedes, 15 own Toyota and 5 own both. How many staff are there in the office?

A. 25

B. 30

C. 35

D. 45

Detailed Solution

M = Mercedez; T = Toyota

Number of staff = 0 + (20 - 5) + (15 - 5) + 5

0 + 15 + 10 + 5 = 30
41.

If the perimeter of \(\bigtriangleup\)PQR in thr diagram is 24cm, what is the area of \(\bigtriangleup\)PRS?

A. 19.5cm2

B. 15.0cm2

C. 13.0cm2

D. 9.3cm2

Detailed Solution

Perimeter of \(\bigtriangleup\) PQR = PQ + QR + PR

24cm = 6cm + 8cm = PR

24 = 14 + PR

PR = 24 - 14 = 10cm

Area of \(\bigtriangleup\) PRS = \(\frac{1}{2} \times 10 \times 3cm^3\)

= 15cm3
42.

In the diagram, PX is a tangent to the circle and RST is an equilateral triangle. Calculate < PTS

A. 60o

B. 90o

C. 120o

D. 150o

Detailed Solution

\(\bigtriangleup\) RST is equilateral triangle, hence

< TRS = < RTS = < RSt = 60o

But < PTR = 60o(Angle between a chord and a tangent at the point of contact = Angle in the alt. segment). From the diagram < PTS = < PTR + < RTS

= 60o + 60o = 120o
43.

In the diagram, < QPR = 60o

< PQR = 50o

< QRS = 2xo

< SRP = 3xo

< UQP = yo and RS//TU

calculate y

A. 102o

B. 78o

C. 70o

D. 60o

Detailed Solution

< RQT = < QRS = 2x (Alternate angles). But in \(\bigtriangleup\) PRQ

50 + 60 + (2x + 3x) = 180o(Angles in a triangle)

110 + 5x = 180o

5x = 180o - 110 = 70o

x = \(\frac{70}{5}\) = 14o

Also y + 50 + 2(14) = 180o

y + 50 + 28 = 180o

y = 180 - 78

44.

In the diagram, find the size of the angle marked a°

A. 60o

B. 80o

C. 120o

D. 160o

Detailed Solution

2 x s = 280°(Angle at centre = 2 x < at circum)

S = \(\frac{280^o}{2}\)

= 140°

< O = 360 - 280 = 80°

60 + 80 + 140 + a = 360°

(< in a quad); 280 + a = 360

a = 360 - 280

a = 80°
45.

Every staff in an office owns either a Mercedes and/or a Toyota car. 20 own Mercedes, 15 own Toyota and 5 own both. How many staff are there in the office?

A. 25

B. 30

C. 35

D. 45

Detailed Solution

M = Mercedez; T = Toyota

Number of staff = 0 + (20 - 5) + (15 - 5) + 5

0 + 15 + 10 + 5 = 30