yogi_Compute Row By Row Sum Of 4 Two Digit Numbers With Plus Sign Between Them

                                         Google Spreadsheet   Post  #1530
Yogi Anand, D.Eng, P.E.      ANAND Enterprises LLC -- Rochester Hills MI     www.energyefficientbuild.com.   Feb-15-2014
post by Boryz (https://productforums.google.com/forum/#!topicsearchin/docs/Hyde%7Csort:date%7Cspell:true/docs/cEC3VnPA6SE) 
How to force google sheets to treat a form answer as numbers/equations

Hello, 

In one of the form question in a form I'm making the answer can sometimes be an equation, i.e. "30+40+20+20" (which is actually a number of bonuses a person acquired during a certain time) . The thing is, if i use that cell in calculations, it treats 30+40+20+20 as a text (or at least not as numbers) and this produces an error.

Is there a google sheets formula that will change the answer to numbers? I wouldn't want to make people to write each number in different cell in order to sum them up, and changing cell format to number doesn't work.

Or maybe if I ask them to write it in a specific way it will work ? 

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