We are trying to average the numbers in one column only if they equal any
or all of 6 different numbers from a different column (7474, 7921, 8612,
9011, 3945, 2209).

We are using this formula, but it seems to be giving us slightly different
numbers than if we just pulled the numbers together through sorting and took
the average.
=AVERAGE(IF(B1:B9={7474, 7921, 8612, 9011, 3945, 2209},C1:C9,FALSE))