Q43 of 43 Page 15

(iii) The student has opted NSS but not NCC.


Let E, F denote the events that a student has opted for NCC and NSS, respectively.

We have, P(E) = =

P(F) = = and

P(E ∩ F) = =

(i) P(E or F) = P(E ∪ F)

                 = P(E) + P(F) - P(E ∩ F)

                 =

                 = =

                 =

Hence, P(E ∪ F) =

(ii) P(E ∪ F)’ = 1 – P(E ∪ F)

                  = 1 -

                  = =

(iii) P(E’ ∪ F) = P(F) – P(E ∩ F) =

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