There were 9 more girls than boys in the classroom. Excluding 6 boys, the number of boys was
45 of the number of girls. When another 7 girls joined, what fraction of the students were girls in the end? Give your answer in its simplest form.
|
Girls |
Boys |
Comparing girls and boys at first |
9 more |
|
Before |
5 u |
4 u + 6 |
Change |
+ 7 |
|
After |
5 u + 7 |
4 u + 6 |
Number of girls at first was 9 more than the number of boys. If another 9 boys entered the classroom at first, the number of girls and boys at first would be the same.
5 u = 4 u + 6 + 9
5 u - 4 u = 6 + 9
1 u = 15
Total number of girls in the end
= 5 u + 7
= 5 x 15 + 7
= 75 + 7
= 82
Total number of students in the end
= 5 u + 7 + 4 u + 6
= 9 u + 13
= 9 x 15 + 13
= 148
Fraction of the students who were girls in the end
=
82148 =
4174 Answer(s):
4174