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1996 Tournament Of Towns
(513) 6
(513) 6
Part of
1996 Tournament Of Towns
Problems
(1)
TOT 513 1996 Autumn J A6 36 numbers in mathlotto
Source:
8/16/2024
The integers from
1
1
1
to
36
36
36
are written on a “mathlotto” ticket. When you buy a “mathlotto” ticket, you choose
6
6
6
of these
36
36
36
numbers. Then
6
6
6
of the integers from
1
1
1
to
36
36
36
are drawn, and a winning ticket is one which does not contain any of them. Prove that(a) if you buy
9
9
9
tickets, you can choose your numbers so that regardless of which numbers are drawn, you are guaranteed to have at least one winning ticket; (b) if you buy only
8
8
8
tickets, it is possible for you not to have any winning tickets, regardless of how you choose your numbers.(S Tokarev)
combinatorics