Question 315393: Two balanced dice are rolled. What is the probability that the sum is six or a "doubles" rolled?
Answer by Fombitz(32388)   (Show Source):
You can put this solution on YOUR website! There are 36 possible outcomes.
(1,5) (2,4) (3,3) (4,2) (5,1): 5 possible outcomes sum to 6.
There are 6 possible doubles. (1,1) (2,2)...(6,6)
P(Sum=6)=5/36
P(Doubles)=6/36
P(Sum=6 or Doubles)=5/36+6/36-1/36.
1/36 is subtracted since (3,3) is counted twice, once as the sum of 6 and again as the double.
P(Sum=6 or Doubles)=10/36=5/18
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