There was an equal number of girls and boys at the gymnasium. After
29 of the girls and 35 boys left the gymnasium, there were 11 more girls than boys at the gymnasium. How many students were there at the gymnasium at first?
| |
Girls |
Boys |
| Before |
9 u |
9 u |
| Change |
- 2 u |
- 35 |
| After |
7 u |
9 u - 35 |
Number of girls in the end
= 9 u - 2 u
= 7 u
If another 11 boys entered the gymnasium, the number of girls and boys would be the same.
9 u - 35 + 11 = 7 u
9 u - 24 = 7 u
9 u - 7 u = 24
2 u = 24
1 u = 24 ÷ 2 = 12
Number of students in the gymnasium at first
= 18 u
= 18 x 12
= 216
Answer(s): 216
