There was an equal number of boys and girls in the school hall. When 20% of the girls left the school hall, there were 9 more boys than girls remaining in the school hall. How many children remained in the school hall?
|
Boys
|
Girls
|
Before
|
5 u
|
5 u
|
Change
|
|
- 1 u
|
After
|
5 u
|
4 u
|
20% =
20100 =
15Number of girls in the end
= 5 u - 1 u
= 4 u
Number of more boys than girls remaining in the school hall
= 5 u - 4 u
= 1 u
1 u = 9
Total number of students remaining in the school hall
= 5 u + 4 u
= 9 u
= 9 x 9
= 81
Answer(s): 81