hard task

klawesyn28@mail.com · science forum beginner Joined: 18 Sep 2005 Posts: 25

I don't know how to solve this task:

Participants of math competition are solving six tasks. For each task
you can get one of marks - 6,5, 3 or 0 .
It transpired that for each pair of participants we can indicate two
tasks , that in each of them participant A got different mark from
participant B.
Delimit the highest number of participants for which this situation is
possible.

Could anybody help me?

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