Question

Two cards are drawn at random. Find the probability that both the cards are of red colour or they are queen. 

Answer 1

Let S = Sample – space. 

 A = The event that the two cards drawn are red. 

B = The event that the two cards drawn are queen. 

A∩ B = The event that the two cards drawn are queen of red colour. |S|=C (52,2), |A| =C (26,2), |B| =C (4,2) 

n(A∩ B) =C (2,2) 

P(A) = |A| / |S|=C (26,2) /C (52.2) , P(B) = |B| / |S|=C (4,2) / C(52,2) 

P(A B) = |A∩ B| / |S|= C(2,2) /C (52,2) 

P(A⋃ B) = ? 

We have P(A⋃ B) = P(A) + P(B) – P(A∩ B) = C(26,2) /C (52.2)+C( 4,2) / C(52,2)–C (2,2) /C (52,2) = 55/221