A king comes from a family of two children. What is the probability that his sibling is a sister?
23
Since the king comes from a family of two children, the total possibilities are (Boy,Boy),(Boy,Girl),(Girl,Boy),(Girl,Girl)
Since one of the two children is already a king (Boy)
Therefore, sample space =(Boy,Boy),(Boy,Girl),(Girl,Boy)
Favorable outcome =(Boy,Girl),(Girl,Boy)
Therefore probability =23