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A die is rolled twice. What is the probability of showing a 3 on the first roll 
and an even number on the second roll?
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First event, showing a 3 on the first roll, has the probability of  .
Second event, showing an even number on the second roll, has the probability
.
Second event, showing an even number on the second roll, has the probability   =
 =  .
These events are independent, so the answer to the problem question is the product
of individual probabilities  P =
.
These events are independent, so the answer to the problem question is the product
of individual probabilities  P =  =
 =  .
.
Solved and explained.