Conditional Average From Mult. Worksheets
 

I have (at least) sixty worksheets. The first 59 are identical formats with different data in cells. (Each one represents a person's statistics).

In a cell (B38) on worksheet 60, I want to get the average of cells P10 from the first 59 worksheets only if cells P15 on each of those sheets = "F".

So, if one of the worksheets does not have "F" in P15, I do not want to include B10 from that worksheet in the average.

What do I enter into Worksheet 60, B38 to show the average that I am looking for?