Challenge Problem 9/25-9/27

Here's this week's challenge problem! Solve this problem with family or friends and bring your answer to class. Remember to turn it in (with your NAME) to the clear box in the classroom. All answers are due by the end of the school day on Friday. Good Luck and Happy Solving!!

 

If there are 20 people at the party and each person shakes hands with everyone there, how many handshakes are there? (Don’t shake your own hand.)