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Construction GC Study – Summation of multiple multiplications in one formula

I am working on creating a general conditions (labor hour) study for a construction project. Its going to calculate the hours worked per employee based on how much of their time (%) is being charged to the job.

To calculate the total hours worked over the course of the job, I need the excel function to multiply each employee’s % time allotted to the project with the number of working hours in the month, and then sum them all up. I have started the formula manually in the image below.

Is there a way to do this without going cell by cell?

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