Q9 of 25 Page 15

If two coins are tossed together. Find the probability of:

(i) Getting exactly two heads


(ii) Getting at least one tails

Concept Used:


When n number of coins are tossed together, Sample space = 2n


When two coins are tossed, sample space = 22 = 4



Explanation:


Sample space = {(H, H), (H, T), (T, H), (T, T)}


(i)


Number of outcomes in which we get exactly two heads = 1 {(H, H)}



(ii)


Getting at least one tails: This means the observations that contain one and more than one tails.


Number of outcomes with at least one tails = 3 {(H, T), (T, H), (T, T)}



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