There are 5 people in a room. On average, each person shakes hands with every other person exactly once. How many handshakes occur?
Q1. There are 5 people in a room. On average, each person shakes hands with every other person exactly once. How many handshakes occur?
Answer: 10
Explanation: The formula to calculate handshakes (or combinations) is n(n-1)/2, where n is the number of people. So, 5(5-1)/2 = 5*4/2 = 10.