There were 8 more girls than boys in the computer lab. Excluding 4 boys, the number of boys was
45 of the number of girls. When another 5 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 |
8 more |
|
Before |
5 u |
4 u + 4 |
Change |
+ 5 |
|
After |
5 u + 5 |
4 u + 4 |
Number of girls at first was 8 more than the number of boys. If another 8 boys entered the computer lab at first, the number of girls and boys at first would be the same.
5 u = 4 u + 4 + 8
5 u - 4 u = 4 + 8
1 u = 12
Total number of girls in the end
= 5 u + 5
= 5 x 12 + 5
= 60 + 5
= 65
Total number of pupils in the end
= 5 u + 5 + 4 u + 4
= 9 u + 9
= 9 x 12 + 9
= 117
Fraction of the pupils who were girls in the end
=
65117 =
59 Answer(s):
59