There were 5 more girls than boys in the music room. Excluding 10 boys, the number of boys was
23 of the number of girls. When another 9 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 |
5 more |
|
Before |
3 u |
2 u + 10 |
Change |
+ 9 |
|
After |
3 u + 9 |
2 u + 10 |
Number of girls at first was 5 more than the number of boys. If another 5 boys entered the music room at first, the number of girls and boys at first would be the same.
3 u = 2 u + 10 + 5
3 u - 2 u = 10 + 5
1 u = 15
Total number of girls in the end
= 3 u + 9
= 3 x 15 + 9
= 45 + 9
= 54
Total number of pupils in the end
= 3 u + 9 + 2 u + 10
= 5 u + 19
= 5 x 15 + 19
= 94
Fraction of the pupils who were girls in the end
=
5494 =
2747 Answer(s):
2747