In a school, the ratio of adults to the number of children is 10 : 1.
The ratio of the number of boys to the number of girls is 8 : 5.
There are 75 more boys than girls.
How many people are there in the school?
| Adults |
Children |
| 10 x 13 |
1 x 13 |
| |
Boys |
Girls |
| |
8 x 1 |
5 x 1 |
| 130 u |
8 u |
5 u |
The number of children is the combined repeated identity.
Make the number of children the same using the LCM of 1 and 13.
LCM of 1 and 13 = 13
Number of more boys than girls
= 8 u - 5 u
= 3 u
3 u = 75
1 u = 75 ÷ 3 = 25
Number of people
= 130 u + 8 u + 5 u
= 143 u
= 143 x 25
= 3575
Answer(s): 3575
