Let’s start the week with a little brain teaser!

Sonya recently created a group for people who love math. The members are introducing themselves and shaking hands so that every member will shake hands with all the others only once.

How many handshakes in total would there be if Sonya’s group was of 19 people?

4 people?

5 people?

6 people?

7 people?

24 people?

Would you like some more? Visit NETMATH to solve other puzzles.