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How Many Handshakes?
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- How Many Handshakes?,
a selection of answers from the Dr. Math archives.
- How Many Handshakes?
- There are 40 people in a room. They shake each other's hands once
and only once. How many handshakes are there altogether?
- Handshake Problem
- If you have n people in a group and each shakes everyone else's
hand only once, how many handshakes take place?
- Math Poster: Handshakes
- If there are 15 people in the room and each person shakes hands with
every other person, how many handshakes will there be?
- Handshakes at a Party
- At a party, everybody shakes hands with each other once. There are
45 handshakes. How many people are there at the party?
- Shaking Hands - How many were
at the party?
- Each person shook hands with everyone else. Mr. Li shook hands with
3 times as many men as women. Mrs. Li shook hands with 4 times as many
men as women.
- Handshakes and Polygon Diagonals
- If a polygon has 42 sides, how many diagonals does it have?
- Handshake Problem Variant
- Five couples go to a party and start shaking hands. One of the men
shouts, "Stop! How many hands did you shake?" Every person gives a
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