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# Combi-natrics-2

How many subsets $$A$$ of $$\{1,2,3,.....,100\}$$ have the property that no three elements of $$A$$ sum to $$101?$$

Note by Ayush Rai
1 year, 4 months ago

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There are 2^10 such subsets. Since 1+2+... + 10 = 55, there is no subset that sums to 101.

Instead of posting each of these problems as individual notes, my suggestion would be for you to post them together in a single note.

- 1 year, 4 months ago

i have edited the question.try it and also the other two parts of combinatrics.

- 1 year, 4 months ago

good one! i will surely make it in a single note.

- 1 year, 4 months ago