perplexus.info :: Numbers : Erase the right 90

Erase the right 90 (Posted on 2016-01-28)

101 distinct real numbers are written in any order

Prove that it is possible to erase 90 of them leaving a sequence of 11 numbers that are in either a strictly increasing or strictly decreasing order.

No Solution Yet Submitted by Ady TZIDON

Rating: 4.0000 (1 votes)

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proof on the internet (spoiler)

| Comment 1 of 5

There is a proof at

which I do not necessarily understand. This proof (generalized for all n+1, where in this case n=10) is the first page of an 11-page paper.

Perhaps there would be a simpler way of explaining it.

Edited on January 28, 2016, 3:19 pm

Posted by Charlie on 2016-01-28 15:16:54

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