SRI LANKAN INTERNATIONAL SCHOOL

RIYADH

Second Semester Examination - 2012/2013

Mathematics

(This paper has 25 questions on`

Admission no: Grade: 8 A/B

1. Make the subject of = 2 -3

(3)

2. Show the following inequalities on the given graph.

x 3

y x

y 2x 1

(5)

3.

A field is in the shape of a rectangle.

The width of the field is 28 metres, measured to the nearest metre.

(a) Work out the upper bound of the width of the field.

......................... metres

(1)

The length of the field is 145 metres, measured to the nearest 5 metres.

(b) Work out the upper bound for the perimeter of the field.

......................... metres

(3)

3.

4.

(i) 7 6 x = 11 10 x

(ii) 3(1 5 x) ( x -2)= 11 9 x

(4)

5. The following diagram shows two straight lines , m and n.

Find the equation of each of the straight lines

(6)

5. Simplify

(3)

7.

Ranis weekly pay this year is $60. This is 20% more than her weekly pay last year.

Jeff says this means Ranis weekly pay last year was $48.

Jeff is wrong.

(a) Explain why

(2)

(b) Work out Ranis weekly pay last year.

(3)

6.

Work out 2 -

(2)

Determine the measure of the unknown angle in each triangle. Round answers to the nearest tenth of a unit.

a) Q 9 cm R

5.5 cm

q

P

b)\

11.4 mm

x

K10.4 mmH

7.

Simplify fully 2a3b a2b6

(2)

Simplify fully

(2)

8.

Multiply out 8(y + 3)

............................................................................................................................................

(1)

1 (b) Factorise 4 2

............................................................................................................................................

(2)

9.

The speed time graph below shows the movement of a trolley for a period of 16 seconds.

(a) Find the period of time when the trolley moves at a uniform speed.

(b) State the rate of change in speed in the last 4 seconds.

(c) If the total distance travelled in the 16 seconds is 153 m , find the

value of v .

Speed (m s

-1

(3)

10. The mode of transportation to school for grade 5 students is given below:

(a). How many students walk to school?

(b). How many students travel by bike and car but do not walk?

. How many students took this survey?

(d). How many students use only bikes?

(e). How many students use all the three modes of transportation?

(5)

11.

)

V

10

0 5 6 16

13.

12.

The data in Diagram shows the height, in cm, of 40 students in a class.

145 174 150 153 153 148 175 154

168 171 166 159 169 175 165 169

160 167 155 160 160 143 176 153

161 167 170 148 177 165 167 165

170 156 162 162 161 157 179 165

(a) Using the data in Diagram 8, and a class interval of 5 cm, complete the

following table.

Height (cm)

Frequency

Midpoint

141 145

2

(b) Using the completed table in (a),

(i) state the modal class,

(ii) estimate the mean mark

13.

(a) Complete the following table for the equation y = 2 x 2 5 x 3.

x

3

2

1

0

0.5

1

2

3

4

5

y

30

4

-3

-6

-5

0

9

22

(b) By using a scale 2 cm to 1 unit on the x -axis and 2 cm to 5 units on the y-axis, draw the graph of

y = 2 x 2 5 x 3 for -3 x 5.

(c) From your graph, state

i) the value of y when x = -2.4,

ii) the value of x when 2 x 2 5 x 3 = 0.

14.

Work out length AB as a decimal.

(3)

15. Estimate the answer

(2)

16.

p

Frequency

5

13

15

24

25

34

35

21

45

8

Total

100

The table shows the frequency of the variable p for various values.

(i) Find the mean

(ii) Find the median

(iii) Find the mode

(5)

Trevor measures the angle of elevation to the top of a fir tree to be 63.

(5)

17.ABCDEF is a regular hexagon.

17.

Work out the size of angle x.

18. Work out the value of the following. Give your answer in standard form.a) (3.2 x 104) - (5 x 103)

b) (3.2 x 104) x (5 x 103)

(4)

19. Calculate the value of

(3)