in a family of 11 children the probability that they are all

in a family of 11 children, the probability that they are all girls is 0.05%. what is the probability of at least one boy this family of 11 children

Solution

probability of at least one boy= 1- probability that they are all girls

probability of at least one boy= 1-0.05%=1-0.0005=0.9995=99.95%