There were 12 more girls than boys in the classroom. Excluding 5 boys, the number of boys was
23 of the number of girls. When another 3 girls joined, what fraction of the pupils were girls in the end? Give your answer in its simplest form.
|
Girls |
Boys |
Comparing girls and boys at first |
12 more |
|
Before |
3 u |
2 u + 5 |
Change |
+ 3 |
|
After |
3 u + 3 |
2 u + 5 |
Number of girls at first was 12 more than the number of boys. If another 12 boys entered the classroom at first, the number of girls and boys at first would be the same.
3 u = 2 u + 5 + 12
3 u - 2 u = 5 + 12
1 u = 17
Total number of girls in the end
= 3 u + 3
= 3 x 17 + 3
= 51 + 3
= 54
Total number of pupils in the end
= 3 u + 3 + 2 u + 5
= 5 u + 8
= 5 x 17 + 8
= 93
Fraction of the pupils who were girls in the end
=
5493 =
1831 Answer(s):
1831