In a school, there is a total of 350 people.
30% are adults.
The rest are children.
The number of boys and girls is in the ratio of 2 : 5.
- What percentage of the people are boys?
- How many girls are there?
Adults |
Children |
Total |
3 u |
7 u |
10 u |
|
Boys |
Girls |
|
3 u |
2 u |
5 u |
10 u |
(a)
30% =
30100 =
310 The number of children is the combined repeated identity.
Adults : Children
3 : 10 - 3
3 : 7
Percentage of the people that are boys
=
210 x 100%
= 20%
(b)
Total number of people = 10 u
10 u = 350
1 u = 350 ÷ 10 = 35
Number of girls
= 5 u
= 5 x 35
= 175
Answer(s): (a) 20%; (b) 175