Question

Three families each have three sons and no daughters. Assuming boy and girl babies are equally likely, what is the probability of this event?

Answer 1

three families with three children all boys
parents-2
children-3
total-5 times 3= 15
then boys-3 times three=9

Answer: 9/12
Percentage:75%

Answer 2

I don't think it matters how many families are involved.
You're talking nine live births, and the probability of a
male birth each time is 50% .

So the probability of nine males in nine births is

(1/2)^9 = 1/512 = about 0.195 percent (rounded)