There were 4 more boys than girls in the music room. Excluding 3 girls, the number of girls was
34 of the number of boys. When another 4 boys joined, what fraction of the students were boys in the end? Give your answer in its simplest form.
| |
Boys |
Girls |
Comparing boys
and girls at first |
4 more |
|
| Before |
4 u |
3 u + 3 |
| Change |
+ 4 |
|
| After |
4 u + 4 |
3 u + 3 |
Number of boys at first was 4 more than the number of girls. If another 4 girls entered the music room at first, the number of boys and girls at first would be the same.
4 u = 3 u + 3 + 4
4 u - 3 u = 3 + 4
1 u = 7
Total number of boys in the end
= 4 u + 4
= 4 x 7 + 4
= 28 + 4
= 32
Total number of students in the end
= 4 u + 4 + 3 u + 3
= 7 u + 7
= 7 x 7 + 7
= 56
Fraction of the students who were boys in the end
=
3256 =
47 Answer(s):
47 
