Three trees: What's the chance of having at least one male and one female? **I have 3 trees.** * These particular trees are dioecious (male or female). * I don't know the gender of any of the trees. * The chance of a tree being male or female is 50/50. * I need at least one male and one female for successful pollination to occur. **What are the chances that I have at least one male and one female tree?**

HINT: Let $M$ denotes male tree, $F$ -- female tree. The probability is $$ 1-P(MMM)-P(FFF). $$ But, from independency, $P(MMM)=P(M)P(M)P(M)=(1/2)^3$.

BTW: What are female trees? Have they a hollow? ;-)