Question 9 - Answer

Both = 1/6 = 2/12

Badminton = 1/4 = 3/12              3/12 -2/12 = 1/12 ( Badminton only)

Football = 2/3 = 8/12                  8/12 - 2/12 = 6/12 ( Football only)

1- 1/12 -6/12 - 2/12 = 3/12         3/12 = 90 ( did not play any sport)

90/3 = 30/unit                              30 x 12 = 360

There were 360 boys.