Question 1149008
folder contains less than 100 files. 
When the files are deleted in groups of five there are three leftover.
---> units digit is 3 or 8
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When the files are deleted in groups of nine, there are six left over.

When the files are deleted in groups of eleven there is only one left over.

How many files are in the folder?
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There's no algebraic solution, no formula.
Figure it out.