Question

I roll two dice and get an even number on the first die.What is the probability that sum is more than 9?

Answer 1

Sample space(total cases) is getting even on first die ,
first die can have 2,4,6 second die can have any of 1,2,3,4,5,6
or outcomes 3x6 = 18

For getting sum more than 9 in above case you must get 4 or 6 in first die. Also for 4 in first die you must get 6 in second die. For 6 in first die you can get 4,5,6 in second die.
So favorable outcome = 1 + 3 = 4

So probability = favorable cases / total cases
= 4/18
= 2/9
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