Find the probability distribution of the number of heads when three coins are tossed.

Explanation

Assume `X =`number of heads for the coin.

Sample space `={{HHH}, {HHT}, {HTT}, {TTT}, {HTH}, {THT}, {THH}, {TTH}}`

Hence, `n(S)=8`

For no heads, we have `n(X=0)=1 Rightarrow P(X=0)=frac{1}{8}`

For one heads, we have `n(X=1)=3 Rightarrow P(X=1)=frac{3}{8}`

For two heads,we have `n(X=2)=3 Rightarrow P(X=2)=frac{3}{8}`

similarly, for three heads, we get `n(X=3)=1 Rightarrow P(X=3)=frac{1}{8}`