Page 110 - Cambridge+Checkpoint+Mathematics+Coursebook+9

End-of-unit review

End-of-unit review

1 Work out these percentages. Do not use a calculator.
a 60% of 84 b 90% of 320 c 15% of 42.6 d 31% of 630

2 Without using a calculator, work out:
a 35% of 2000 mm b 40% of 960 kg c 120% of 760 hours.
3 27% of 430 = 116.1

Use this fact to work out:
a 27% of 860 b 2.7% of 430 c 54% of 215 d 13.5% of 4300.
4 This table shows how many men and women in a company cycle to work.
Cycle to work Do not cycle Total

Men 15 41 56
Women 38 82 120
a Work out the percentage of men who cycle to work.
b Work out the percentage of women who
do not cycle to work.
c Read what Dakarai is saying. Men are more likely to cycle to work.
Do the numbers in the table support this
statement? Give a reason for your answer.
5 One year, in school A, 162 students leave and 109 go to university.
In school B, 75 students leave and 68 go to university.
Compare the percentages of students going to university from each school.
6 Work out the results of these changes.
a A crowd of 8000 people increases by 20%.
b The price of a $43 000 car decreases by 6%.
c The mass of a 3.20 kg baby increases by 80%.
7 Read what Mia is saying. A price can increase by 150% but
Explain why she is correct. it cannot decrease by 150%.

8 Before tax, the price of fuel is $3.40 per litre.
Tax of 30% is added.
Work out the cost of 28 litres of fuel, including tax.
9 A trader bought 12 shirts for $150 altogether. He sold 11 them for $20 each and one for $10.
Work out his overall percentage profit or loss.

10 The price of a computer is $695. A shop offers 15% discount.
Work out the discount price.
11 This year Justin earned $52 700.
He must pay 28% tax on everything he earns over $12 800.
a Work out how much tax he has to pay.
b Work out the percentage of his income that he pays in tax.

11 Percentages 109