College Math Teaching

February 21, 2014

Recreational math problem with a spreadsheet

Filed under: recreational mathematics — Tags: , — collegemathteaching @ 4:37 pm

I saw this on Facebook:


Yes, I know, there are different formulas that work. So suppose we want ” 3 + 5″ to “equal” -28. What we want is the first digests (the constant coefficient upwards) to be the sum of the numbers, and the “leading” digits to be “a-b” with a correct sign; that is: a “+” b = (a-b, a+b) with the comma removed so as to make a single integer (the inputs are integers).

So the “cute” problem: get a spread sheet to do this.


To get full credit: you must get the correct answer for both a greater than b and a “less than” b.


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