justin, julie, jamie, matt, ryan, and roland are the six players in a round-robin tennis tournament. each player will play a set against each of the other players. list all the sets that need to be played.

Answer 1

I would list the names vertically.
Justin
Julie
Jamie
Matt
Ryan
Roland.
Now pair up one at a time. For example
Justin/Julie
Justin/Jamie
Justin/Matt
Justin/Ryan
Justin/Roland
Then go to the next one; i.e., Julie.
Omit Julie/Justin because you already have that one.
Julie/Jamie
Julie/Matt
Julie/Ryan
Julie/Roland
etc.

Answer 2

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