Question

Three coins are tossed simultaneously. Find the probability of at least one head and one tail.

(a) \(\frac{1}{2}\)

(b) \(\frac{1}{4}\)

(c) \(\frac{3}{4}\)

(d) None of these

Answer 1

(c) \(\frac{3}{4}\)

The sample space for a simultaneous toss of three coins 

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

Favourable cases = {HHT, HTT, THH, TTH, THT, HTH} 

\(\therefore\) P ( getting at least one head, one tail) =\(\frac{6}{8}\) =\(\frac{3}{4}\).