The ratio of boys to students is that for every 5 students there are 3 boys. We can multiply the numerator and denominator by 9 to get how many boys are there in total out of the 45 students
3*9= 27
5*9= 45
there are 27 boys in the class. To find how many girls there are subtract 27 from 45
45
27
------
18
There are 18 girls in the class
