At a conference, 12 members shook hands with each other before and after the meeting. How many total member of hand shakes occurred?

At a conference, 12 members shook hands with each other before and after the meeting. How many total member of hand shakes occurred?

Explanation

To find the total number of handshakes, we use the combination formula since each member shakes hands with every other member exactly once before and after the meeting.

Number of members = 12

Handshakes before the meeting = 12C2 = (12 × 11) / 2 = 66

Handshakes after the meeting = 66

Total handshakes = 66 + 66 = 132