UPSC Civil Services 2018 Prelims General Studies Paper II

Using venn diagram the given information can be representd as follows:
Let the number of players wearing both hockey shirt and pant be x
∴ n (st+1p) = x, n (s) = 14 – x
n (p) = 11 – x
n (T) = 19 (∴ T = Total number of players)
∴ n (T) = n (s) + n (p) + n (S + P)
∴ 19 = 14 – x + 11 –x + x
∴ 19 = 25 – x
∴ x = 25 – 19 = 6