SOLUTION: the ratio of the number of boys to the number of girls in a class was 2:3 at first. after 4 girls left the class, the ratio became 4:5. how many boys were there in the class

Algebra ->  Percentage-and-ratio-word-problems -> SOLUTION: the ratio of the number of boys to the number of girls in a class was 2:3 at first. after 4 girls left the class, the ratio became 4:5. how many boys were there in the class      Log On


   

Question 392153: the ratio of the number of boys to the number of girls in a class was 2:3 at first. after 4 girls left the class, the ratio became 4:5. how many boys were there in the class
Answer by robertb(5830) About Me  (Show Source):
You can put this solution on YOUR website!
b%2Fg+=+2%2F3 and b%2F%28g-4%29=4%2F5
==> b+=+2g%2F3 and b+=+4%28g-4%29%2F5
==> 2g%2F3+=+4%28g-4%29%2F5
==> 5g = 6g - 24
==>g = 24, the number of girls, and
b = 16, the number of boys.