Three coins are tossed once. Find the probability of getting
(i) 3 heads                  
(ii) 2 heads

Explanation

When three coins are tossed once the sample space is given by

S=HHH,HHT,HTH,THH,HTT,THT,TTH,TTT

∴ Accordingly n(S)=8

It is known that the probability of an event A is given by


P(A)= `(n(A))/(n(S))`


(i) Let B be the event of the occurrence of 3 heads Accordingly B=HHH

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