In a school, the ratio of children to the number of adults is 9 : 10.
The ratio of the number of men to the number of women is 7 : 1.
There are 90 less women than men.
How many people are there in the school?
Children |
Adults |
9 x 4 |
10 x 4 |
|
Men |
Women |
|
7 x 5 |
1 x 5 |
36 u |
35 u |
5 u |
The number of adults is the combined repeated identity.
Make the number of adults the same using the LCM of 10 and 8.
LCM of 10 and 8 = 40
Number of less women than men
= 35 u - 5 u
= 30 u
30 u = 90
1 u = 90 ÷ 30 = 3
Number of people
= 36 u + 35 u + 5 u
= 76 u
= 76 x 3
= 228
Answer(s): 228