At the end of a business conference, the ten people present all shake hands with each other once. How many handshakes will there be altogether?
At the end of a business conference, the ten people present all shake hands with each other once. How many handshakes will there be altogether?
Show Hint
- 20
- 45
- 55
90
The Correct Option is B
Solution and Explanation
For each handshake, two people shake hands. The total number of handshakes can be found using the formula for combinations \( C(n, 2) \), where \( n \) is the number of people: \[ C(10, 2) = \frac{10 \times 9}{2} = 45. \] Thus, the total number of handshakes is 45. So, the correct answer is (b) 45.
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