M May If there are 25 guests, how many handshakes altogether? At a party every guest shakes hands with every other guest once. How many triangles?
M May If there are 25 guests, how many handshakes altogether? At a party every guest shakes hands with every other guest once. Each of 25 people shake hands with 24 other people. Two people for each handshake! 25 x 24 2 = 300 shakes 1st2nd3rd……..24th25th …… …….1 +0 } = 24 x 25 /2/2 = 300 twice twice
M May How many triangles?