Practice problem
Extension: Triangular Numbers
You are at a meeting that has people. Everybody at the meeting shakes hands with everybody else, and nobody shakes hands with the same person more than once. How many handshakes took place in total?
Practice problem
You are at a meeting that has people. Everybody at the meeting shakes hands with everybody else, and nobody shakes hands with the same person more than once. How many handshakes took place in total?