

InterviewSolution
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Three fair coins are tossed together. Find the probability of getting(i) all heads(ii) atleast one tail(iii) atmost one head(iv) atmost two tails |
Answer» Three fair coins are tossed together Sample spade = {HHH, HHT, HTH, HTT, THH, THT, TTH, TTT} n(S) = 8 (i) Let A be the event of getting all heads A = {HHH} n(A) = 1 P(A) = \(\frac{n(A)}{n(S)}=\frac{1}{8}\) (ii) Let B be the event of getting atleast one tail. B = {HHT, HTH, HTT, THH, THT, TTH, TTT} n(B) = 7 P(B) = \(\frac{n(B)}{n(S)}=\frac{7}{8}\) (iii) Let C be the event of getting atmost one head C = {HTT, THT, TTH, TTT} n(C) = 4 P(C) = \(\frac{n(C)}{n(S)}=\frac{4}{8}=\frac{1}{2}\) (iv) Let D be the event of getting atmost two tails. D = {HTT, TTT, TTH, THT, THH, HHT, HTH} n(D) = 7 P(D) = \(\frac{n(D)}{n(S)}=\frac{7}{8}\) |
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