i must make a formula to average a column of numbers but only the numbers
which are narrowed down from two other columns.

for example:

Production Calendar (sheet 1)

john doe Memco SMF $20
joe garcia SMH $13
jessie nelson Memco SMF $10
david toms Memco SMM $ 9


Wage Summary (sheet 2)

average wage of a Memco, SMF employee


The answer would be $15