Q25 of 96 Page 166

A coin is tossed 3 times. List the possible outcomes. Find the probability of getting

(i) all heads


(ii) at least 2 heads

The possible outcomes if a coin is tossed 3 times is

S = {(HHH),(TTT),(HTT),(THT),(TTH),(THH),(HTH),(HHT)}


n(S) = 8


(i) Let E1 = Event of getting all heads = {(HHH)}


∴ n(E1) = 1



(ii) Let E2 = Event of getting atleast 2 heads = {(HHT),(HTH),(THH),(HHH)}


∴ n(E2) = 4



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