help!!!!! Probability!!!
posted by fweng on .
A fair 6sided die is rolled twice. The probability that the second roll is strictly less than the first roll can be written as a/b, where a and b are positive, coprime integers. What is the value of a+b?

Assume die is fair.
Rolling twice gives 36 outcomes, of which the second roll is strictly less than the first (successes) can be enumerated as follows:
21,31,32,41,42,43,51,52,53,54,61,62,63,64,65
Count how many successes there are, and divide by the size of the sample space (36). 
thanks sir...

You're welcome!
It would be even better if you would not use various aliases.