1. How many combinations of 2 hearts are possible?
You can draw 1 of 13 the first time, then 1 of the remaining 12 the second time. So I think there would be 13*12 = 156 ways you could daw 2 hearts in two card draws.

2. Also if a family has three kids what is the probability of having one boy?
=Number of ways you can have one boy / number of combinations possible

Number of ways you can have one boy = 3 choose 1 = 3! / (1!*2!) = 3
Number of combinations possible = 2*2*2 = 8 (A boy or girl each time)
Answer = 3/8

I hope this helps.

- Steve J