Question

In a class,12 pupils are in the band and 3/4 of the remaining pupils are in the modern dance club. If 1/5 of the class are in neither the band nor the club,how many pupils are there in the class?

Answer 1

If there are x students in all, 1/4 of the non-band students are in neither:

1/4 (x-12) = x/5
x/4-3 = x/5
x/20 = 3
x = 60

Check:
12 in band, leaves 48 others
36 in dance club
12 in neither