if there are 11000 people in a room and each person is asked to shake hands with every single other person, how many handshakes will occur?? I'm in year 7 by the way.
11000 people each shake hands with 10999 people so it seems at first as though there would be 11000*10999 handshakes. However, each handshake involves two people so the total number of handshakes is only 11000*10999/2
