There were 5 more girls than boys in the music room. Excluding 3 boys, the number of boys was
34 of the number of girls. When another 4 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 |
4 u |
3 u + 3 |
| Change |
+ 4 |
|
| After |
4 u + 4 |
3 u + 3 |
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.
4 u = 3 u + 3 + 5
4 u - 3 u = 3 + 5
1 u = 8
Total number of girls in the end
= 4 u + 4
= 4 x 8 + 4
= 32 + 4
= 36
Total number of pupils in the end
= 4 u + 4 + 3 u + 3
= 7 u + 7
= 7 x 8 + 7
= 63
Fraction of the pupils who were girls in the end
=
3663 =
47 Answer(s):
47 
