Let A = cricket player and B = football player Then, n(A) = 50%, n(B) = 40%, n(A∪B)=10% ∴n(A∪B)=n(A)+n(B)–n(A∩B) =50+40–10 =90–10=80% ∴ per cent of students play either cricket or football = 80% ∴ per cent of students play neither cricket nor football =100−n(A∪B) =100−80%=20%