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Two numbers $X_1$ and $X_2$ are drawn randomly from the set $\{1,2,...,n\}$ without replacement. Find $P(X_2 > X_1)$.

Now I know that once we choose $X_2$ we have $X_2 - 1$ options for $X_1$ to hold the condition that $X_2 > X_1$ but the fact that we choose $X_1$ first kind of makes me confused.

Any hints please?

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HINT: Since you’re drawing without replacement, you’re drawing two different numbers. Every pair of distinct numbers can be drawn in either order, and either order is equally likely.

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