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Question 1 - handshake:
A married couple organizes a party. They only invite other married couples. At least one person of an invited couple is acquainted to at least the host or the hostess (so between sets {host,hostess} and {male of invited couple, female of invited couple} there exists at least one relation, but two, three or four relations is also possible). Upon arrival at the party, each person shakes hands with all other guests he/she doesn't know yet (it is assumed everybody knows him/herself and his/her partner).

When all couples have arrived and all the handshaking has been done, the host mingles between the guests and ask everybody (including his wife): "How many hands did you shake?". To his surprise, all responses are different.

With the above information, you must be able to determine how many hands the host and hostess each shook. Show Answer

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