Please help,there are b boys in the class.This is three more than four times the number of girls.How many girls are in the class?

Answer 1

Insufficient data to tell the answer numerically:
The equation turns out to be
b = 3+4g ( where g stands for number of girls)
As you can see, there are infinitely many possible answers.
A simple answer would be g = (b-3)/ 4.

Answer 2

g Girls in the class.
4g + 3 Boys in class.

Total = g + (4g+3). The total should have been given.