Solution:
Using the “Problem Solving Process.
”Handshake #2”

1. Understand the problem
1. What data or information is known?
   • 10 people
2. What data or information is unknown?
   • How many hand shakes will occur when everyone will shake hands with everyone else in the room.
3. What are the conditions?
   • Everyone in the room will shake hands once and only once with everyone else in the room.
2. Make a Plan to solve the problem – (This is known as an Algorithm!)
   • H=Number of handshakes.
   • N=Number of people.
   • H = N(N-1)/2
3. Carry out the plan.

   H= (10(10-1)/2

4. Reflect on how the problem was solved.

   Note: The easiest way to test this formula is with 4 people and then 5 people to see if the formula is accurate.

   Eg: 4 People = 6 handshakes

   1,2 2,3 3,4

   1,3 2,3

   1.4