21.(i) In a class of students, opted for NCC, opted for NSS and opted for both NCC and NSS. If one of these students is selected at random, find the probability that
(i) The student opted for NCC or NSS.
Let A be the event that student opted for NCC and B be the event that the student opted for NSS.
Given,
n(S) = 60, n(A) = 30, n(B) =32, n(A B) = 24
Therefore, P(A) =
P(B) =
P(A B) =
(i) We know,
P(A B) = P(A)+ P(B) - P(A B)
Hence,the probability that the student opted for NCC or NSS is