There was an equal number of girls and boys at the auditorium. After
57 of the girls and 53 boys left the auditorium, there were 13 more girls than boys at the auditorium. How many pupils were there at the auditorium at first?
|
Girls |
Boys |
Before |
7 u |
7 u |
Change |
- 5 u |
- 53 |
After |
2 u |
7 u - 53 |
Number of girls in the end
= 7 u - 5 u
= 2 u
If another 13 boys entered the auditorium, the number of girls and boys would be the same.
7 u - 53 + 13 = 2 u
7 u - 40 = 2 u
7 u - 2 u = 40
5 u = 40
1 u = 40 ÷ 5 = 8
Number of pupils in the auditorium at first
= 14 u
= 14 x 8
= 112
Answer(s): 112