if 3/5 of the class are boys and there are 12 more boys than girls. How many girls are there in the class?

Answer 1

3/5-2/5=1/5
So proportion is
1/5 of the class equals 12 students
So the whole class is 5*12=60 students.
# of Girls = 60*2/5=24

Answer 2

3 *12 = 36
5*12 = 60
60-36 = 24