Page 114 - MAT KS3 Y8 Cambridge CheckPoint

11.1 Calculating percentages

8 Use the facts in the boxes to find:
a 74% of X b 48% of X c 61% of X 37% of X is 44.03 24% of X is 28.56
d 18.5% of X e 13% of X.
9 When 420 students took an examination, 80% passed.
a How many passed? b What percentage failed? c How many failed?
10 In an election, 4600 people voted. They had the choice of three parties. The
Red Party: 37%
results are shown in the box.
a How many votes did each of those parties get? Blue Party: 28%
b What percentage of the voters did not vote for those three parties? Yellow Party: 20%

11 There are 40 000 people at a soccer match. 83% support the home team.
a How many people support the home team?
b How many do not support the home team?
c What percentage do not support the home team?

12 a What amounts of copper and tin are there in 30 grams of bronze? The metal bronze is made from
b What amounts of copper and tin are there in one kilogram of 95% copper and 5% tin.
bronze?
13 a What percentage of stainless steel is iron?
Stainless steel is made from 18%
b What amounts of chromium and nickel are there in a
chromium, 8% nickel and the rest
stainless steel knife blade with a mass of 140 g?
is iron.
c The Parliament House of Australia, in Canberra, has a
stainless steel flagpole with a mass of about 200 tonnes.
How much chromium and nickel does it contain? 1 tonne = 1000 kilograms
14 The population of Europe is 850 million.
This table gives the percentage of the population of Europe living in some of its countries.

Country Germany France Spain Sweden
Percentage of European population 9.6% 7.8% 5.5% 1.1%

Estimate the population of each country. Give your answers to the nearest million.

15 There were 5623 people at a music concert. At the concert
Work out the numbers of men, women, boys and girls at the concert.
Girls
13%
Boys Men
21% 42%

Women
24%

16 The population of a town is 32 600.
About 27% are over 60 years old. About 19% are 16 or under. How many are between 16 and 60?
17 Which of these amounts are different from
32% of 48 12% of 128 3% of 512
the others? Give a reason for your answer.
96% of 16 18% of 84 9% of 168
120% of 12.8 24% of 64 1.5% of 1024

112 11 Percentages