In a school, the ratio of children to the number of adults is 7 : 9.
The ratio of the number of men to the number of women is 2 : 1.
There are 84 less women than men.
How many people are there in the school?
Children |
Adults |
7 x 1 |
9 x 1 |
|
Men |
Women |
|
2 x 3 |
1 x 3 |
7 u |
6 u |
3 u |
The number of adults is the combined repeated identity.
Make the number of adults the same using the LCM of 9 and 3.
LCM of 9 and 3 = 9
Number of less women than men
= 6 u - 3 u
= 3 u
3 u = 84
1 u = 84 ÷ 3 = 28
Number of people
= 7 u + 6 u + 3 u
= 16 u
= 16 x 28
= 448
Answer(s): 448