There was an equal number of boys and girls at the gymnasium. After
29 of the boys and 46 girls left the gymnasium, there were 18 more boys than girls at the gymnasium. How many students were there at the gymnasium at first?
| |
Boys |
Girls |
| Before |
9 u |
9 u |
| Change |
- 2 u |
- 46 |
| After |
7 u |
9 u - 46 |
Number of boys in the end
= 9 u - 2 u
= 7 u
If another 18 girls entered the gymnasium, the number of boys and girls would be the same.
9 u - 46 + 18 = 7 u
9 u - 28 = 7 u
9 u - 7 u = 28
2 u = 28
1 u = 28 ÷ 2 = 14
Number of students in the gymnasium at first
= 18 u
= 18 x 14
= 252
Answer(s): 252
