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# Probability

Let $$A = \{1,2,3,\ldots,n \}$$ and $$B = \{1,2,3,\ldots,n\}$$. Random numbers $$i$$ and $$j$$ are chosen from the sets $$A$$ and $$B$$, respectively. Find the probability of $$i \geq j$$. That is, what is $$P(i \geq j)$$?

Note by Aniket Sen
1 year, 6 months ago

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We have $n^2$ outcomes and $n^2+n\over 2$ are good one. So $P(i\geq j) = {n+1\over 2n}$

- 7 months, 3 weeks ago