yogi_Compute Average Of Numbers In Specified Columns By Row

Yogi Anand, D.Eng, P.E.                                         Google Spreadsheet                            www.energyefficientbuild.com

bztkd said:
Averaging Columns
I have a spreadsheet with 6 columns.

I need Column F to be the average of Columns C,D and (sometimes) E. If E is not to be included in the average the cell will be left blank. Columns C,D, and E are all numbers. How do I go about doing this?

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