When a coin is tossed twice the sample space is * = {HH,HT, TH,TT}
Let x denote the number of heads in any out come in *.
∴ x(HH) = 2
x(HT) = 1
x(TH) = 1
x(TT) = 0
P(x = 0) = P(TT) = 1/4
P(x = 1) P(HT,TH) = 2/4 = 1/2
P(x = 2) P(HT,TH) = 1/4
Probability distribution of x is
