In a school, there is a total of 600 people.
40% are adults.
The rest are children.
The number of boys and girls is in the ratio of 1 : 4.
- What percentage of the people are boys?
- How many girls are there?
Adults |
Children |
Total |
2x5 |
3x5 |
5x5 |
|
Boys |
Girls |
|
|
1x3 |
4x3 |
|
10 u |
3 u |
12 u |
25 u |
(a)
40% =
40100 =
25 Adults : Children
2 : 5 - 2
2 : 3
Boys : Girls : Children
1 : 4 : 5
The number of children is the combined repeated identity.
Make the number of children the same using the LCM of 3 and 5.
LCM of 3 and 5 = 15
Percentage of the people that are boys
=
325 x 100%
= 12%
(b)
Total number of people = 25 u
25 u = 600
1 u = 600 ÷ 25 = 24
Number of girls
= 12 u
= 12 x 24
= 288
Answer(s): (a) 12%; (b) 288