Probability Q31

31. Three unbiased coins are tossed.What is the probability of getting at least 2   heads?

             A.  1/2         B.  1/4

            C.  1/3           D.  1/8

Answer:

Here S= {TTT, TTH, THT, HTT, THH, HTH, HHt, HHH}.

Let E = event of getting at least two heads = {THH, HTH, HHT, HHH}.

P(E)   = n(E) / n(S)

= 4/8.

‹=›1/2.