In a school, there is a total of 140 people.
40% are adults.
The rest are children.
The number of girls and boys is in the ratio of 1 : 5.
- What percentage of the people are girls?
- How many boys are there?
Adults |
Children |
Total |
2x2 |
3x2 |
5x2 |
|
Girls |
Boys |
|
|
1x1 |
5x1 |
|
4 u |
1 u |
5 u |
10 u |
(a)
40% =
40100 =
25 Adults : Children
2 : 5 - 2
2 : 3
Girls : Boys : Children
1 : 5 : 6
The number of children is the combined repeated identity.
Make the number of children the same using the LCM of 3 and 6.
LCM of 3 and 6 = 6
Percentage of the people that are girls
=
110 x 100%
= 10%
(b)
Total number of people = 10 u
10 u = 140
1 u = 140 ÷ 10 = 14
Number of boys
= 5 u
= 5 x 14
= 70
Answer(s): (a) 10%; (b) 70