In a school, the ratio of adults to the number of children is 7 : 6.
The ratio of the number of girls to the number of boys is 2 : 1.
There are 84 more girls than boys.
How many people are there in the school?
Adults |
Children |
7 x 1 |
6 x 1 |
|
Girls |
Boys |
|
2 x 2 |
1 x 2 |
7 u |
4 u |
2 u |
The number of children is the combined repeated identity.
Make the number of children the same using the LCM of 6 and 3.
LCM of 6 and 3 = 6
Number of more girls than boys
= 4 u - 2 u
= 2 u
2 u = 84
1 u = 84 ÷ 2 = 42
Number of people
= 7 u + 4 u + 2 u
= 13 u
= 13 x 42
= 546
Answer(s): 546