In a school, the ratio of children to the number of adults is 6 : 5.
The ratio of the number of men to the number of women is 4 : 3.
There are 100 more men than women.
How many people are there in the school?
| Children |
Adults |
| 6 x 7 |
5 x 7 |
| |
Men |
Women |
| |
4 x 5 |
3 x 5 |
| 42 u |
20 u |
15 u |
The number of adults is the combined repeated identity.
Make the number of adults the same using the LCM of 5 and 7.
LCM of 5 and 7 = 35
Number of more men than women
= 20 u - 15 u
= 5 u
5 u = 100
1 u = 100 ÷ 5 = 20
Number of people
= 42 u + 20 u + 15 u
= 77 u
= 77 x 20
= 1540
Answer(s): 1540
