# Uniform random variable

Let X and Y be independent and uniform on {1, 2, ... M}
Find P(X > Y)

so i know that P(X = x) = 1/M and P(Y = y) = 1/M
i don't understand how Find P(X > Y) = (M+1)/2M

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Hi magnifik!

Suppose M=3.

Then we have the matrix:
Code:
X\Y   1  2  3
1     ≥
2     ≥  ≥
3     ≥  ≥  ≥
In how many cases is the condition satisfied?
And what is the total number of cases?