Question:medium

From a set \(\{1,2,3,4,5,6,7\}\) two numbers are selected at random. The random variable \(X\) is defined as the absolute difference of the numbers selected. The mean of \(X\) is

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For a set of consecutive integers from \(1\) to \(n\), the expected absolute difference of two randomly chosen numbers is always given by the shortcut formula \(\frac{n+1}{3}\).
Here, \(\frac{7+1}{3} = \frac{8}{3}\).

Updated On: Jun 23, 2026

\(21\)
\(4\)
\(\frac{8}{3}\)
\(\frac{7}{2}\)

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The Correct Option is C

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