Question

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 ?

• A. $20$
• B. $45$
• C. $55$
• D. $90$

Answer 1

The correct option is B $45$

Clearly, total number of handshakes $=(9+8+7+6+5+4+3+2+1)=45$.