SOLUTION: Given the set (1,1,2,4,7,13,24,44,81), how many integers between 3 and 85 cannot be written as the sum of three elements in the set?

Question 1186691: Given the set (1,1,2,4,7,13,24,44,81), how many integers between 3 and 85 cannot be written as the sum of three elements in the set?
Answer by greenestamps(13216) (Show Source): You can put this solution on YOUR website!

If there is a formal way to answer this question using algebra, it would be exceedingly messy.

Answering the question simply involves doing the work in a systematic way; you can spend your time doing it as easily as we can.

There are two very different methods to methodically go about finding which integers from 3 to 85 can and cannot be written as the sum of three of the elements:
(1) look at every integer from 3 to 85 and see whether or not it can; or
(2) look at every possible sum of three of the elements of the set

The first method is probably less desirable, since it will be easy to either overlook a sum that can be made or make errors to conclude incorrectly that you can make a sum which in fact you can't.

If you use the second method methodically, you should have a very good chance of ending with the right answer.

No; I didn't finish the problem, so I don't have the answer for you. Though I know HOW to find the answer, I choose not to spend my valuable time actually working the problem to its end.

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