How do I find the probability of the complement of B?

#1
New here...

How do I find the probability of the complement of B? Here is the full question:
If B is the event of a child having brown hair, find the probability of the complement of B. (Enter your answer as a fraction.)

I don't want the answer, which is why I did not enter all the data. I want to know how to do it so I can figure it out myself.

Thanks!
 
#3
Complements can be tricky, I know I used to struggle with them before I got a hang of them. The complement is simply everything else but a certain event (in this case a child having brown hair). So the complement is the probability of a child having everything BUT brown hair. As Dason points out, use what you know about the sum of all probabilities to find the probability of the complement.