# Summing the multiplication of two columns

Hello,

I would like to know how to use a formula to multiply two columns and sum the results over multiple rows.

My columns are "salary" and "percent_work" (that is, 1.0 = full time, 0.5 = half time, etc.). My rows are the employees.

I need to multiply salary * percent_work and sum over all employees to obtain the total amount of payroll. Is there a formula for that?

Thanks

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Hey @Ligia

The easiest way to do this is to add a helper column for the multiplication

=salary@row * [percent_work]@row

The sum, which if desired could be collected in a Sheet Summary field (found in the right hand menu on sheet) since it is a single value for the entire sheet, becomes

=SUM([helper column]:[helper column])

Be sure to change all the column references to your actual column names

Does this work for you?

Kelly

• Hi Kelly,

Thank you for your answer. I am hoping there is a way to do this without a helper column. The reason is that I need to do this operation for about 25 columns, so that would mean adding 25 helper columns.

Is it possible to do this without a helper column?

Thanks,

Ligia

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Maybe other community members can provide alternatives. The 25 other columns- are these separate arithmetic operations? Can some/all of the operations be combined in a single or few formula(s)?

• The 25 columns are different projects. Each employee works on one or more projects.

Thanks for trying to help.

Ligia

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