Question

The probability of getting atmost two heads when three coins are tossed is 

A) 1/8

B) 8 

C) 7/8

D) 3/8

Answer 1

Correct option is (C) 7/8

If three coins are tossed then possible outcomes are S = {HHH, HHT, HTH, THH, HTT, THT, TTH, TTT}

\(\therefore\) Total outcomes is n(S) = 8

Let event E be event of getting at most two heads.

\(\therefore\) E = {HHT, HTH, THH, HTT, THT, TTH, TTT}

\(\therefore\) n(E) = 7

\(\therefore\) P(E) \(=\frac{n(E)}{n(S)}=\frac78\)

Hence, the probability of getting at most two heads is \(\frac{7}{8}.\)

Answer 2

Correct option is  C) 7/8