Question

Jonathan’s class has 30 boys. Of the students in his class, 60% are girls. How many girls are in Jonathan’s class?

Answer 1

let the number of students in Jonathan's class be x
60%+40%=100%
boys are 40%
40%=30
40=30÷x×100
40×x=30×100
x=3000÷40
x=75
therefore there are 75 students in Jonathan's class
total students=girls+boys
75=girls+30
girls=75-30
girls=45
Hence there are 45 girls in Jonathan's class