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Everybody in a room shakes hands with everybody else. The total number of handshakes is 66. The number of persons in the room is

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Number of handshakes among $n$ persons $= \dbinom{n}{2} = \dfrac{n(n-1)}{2}$. Solve the resulting quadratic for $n$.

Updated On: Apr 8, 2026

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The Correct Option is B

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Everybody in a room shakes hands with everybody else. The total number of handshakes is 66. The number of persons in the room is

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The Correct Option is B

Solution and Explanation

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