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 Question from Jeff: need pairing for 10 golfer playing 5 rounds of golf.

Jeff,

Do you want a foursome and two threesomes? Here is a schedule like that for 10 players where everyone plays together once or twice over 5 rounds. It is the best you can do. Some pairs need to play together more than once, and not everyone can play together twice.

JABC DEF GHI;
AHF JDBI GEC;
JEGH ACG BFI;
JAEI BFG CDH.

Have fun,
Victoria

In March 2011 Ken wrote the following note to us

Question from Ken, a teacher:

Victoria answered this question but on round 4 she has used golfer G twice( there is no golfer D. I can't find a combination where golfers 9 and 10 don't plat together less than three times. Can you correct this ?

Victoria responded.

He's right. I think it can be fixed. Start with the same first three rounds as before:

JABC DEF GHI;
AHF JDBI GEC;

Then use:

JAEG BFI CDH;
BFG ACEI JHD

and jumble up the days to separate the repeats that occur in the last two lines.

If I read this right, all pairs play together once and then:
A plays with C, E, G and J twice.
B plays with F, I and J twice.
C plays A, E, I, and J twice.
D plays with H and J twice.
E plays with A, C and G twice.
F plays with B and I twice.
G plays with A and E twice.
H plays with D twice.
I plays with B, C, F and J twice.
J plays with A, B, C, D, and I twice.

So no pairs play together three times. It may not be a perfect schedule (i.e. best possible). It seems not bad though.

--Gary

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