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counting and probability intermediate

Problem

Two fair 6-sided dice are rolled. What is the probability at least one of the dice shows a 1?
Solution
There are 5 ways in which the first roll is not 1, and 5 ways in which the second roll is not 1, so there are ways in which neither die shows 1. Therefore there are ways in which one or both dice show 1. So the probability of this is .
Final answer
\dfrac{11}{36}