more rolling dice

Question

involving the sum of two die rolls.
(1) What is the probability they sum to 11, 7, or 8?

 

(2) What is the probability they sum to at least 6?

Answer 1

here is the sample space for rolling 2 dice

 

2 3 4 5 6 7

3 4 5 6 7 8

4 5 6 7 8 9

5 6 7 8 9 10

6 7 8 9 10 11

7 8 9 10 11 12

there are 36 outcomes and 2 11s, 6 7s, and 5 8s

the probability is (2+6+5)/36=13/36

 

at least 6 means 6, 7, 8, 9, 10, 11, or 12

26/36=13/18