There were 5 more boys than girls in the tuck shop. Excluding 9 girls, the number of girls was
34 of the number of boys. When another 7 boys joined, what fraction of the pupils were boys in the end? Give your answer in its simplest form.
|
Boys |
Girls |
Comparing boys and girls at first |
5 more |
|
Before |
4 u |
3 u + 9 |
Change |
+ 7 |
|
After |
4 u + 7 |
3 u + 9 |
Number of boys at first was 5 more than the number of girls. If another 5 girls entered the tuck shop at first, the number of boys and girls at first would be the same.
4 u = 3 u + 9 + 5
4 u - 3 u = 9 + 5
1 u = 14
Total number of boys in the end
= 4 u + 7
= 4 x 14 + 7
= 56 + 7
= 63
Total number of pupils in the end
= 4 u + 7 + 3 u + 9
= 7 u + 16
= 7 x 14 + 16
= 114
Fraction of the pupils who were boys in the end
=
63114 =
2138 Answer(s):
2138