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Chapter 1: Q. 1.13 (page 16)

Consider a group of 20people. If everyone shakes hands with everyone else, how many handshakes take place?

Short Answer

Expert verified

Total number of handshakes=190.

Step by step solution

01

Step 1. Given information.

No. of persons = 20

Everyone shakes hands with everyone else.

02

Step.2 Calculate the possible number of handshakes.

No. of combinations, which can be formed out of 20people taking 2at a time is given by 202.

=20!2!18!=20×19×18!2×1×18!=10×19=190

Therefore, the possible no. of handshakes are=190.

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