Average formula query

[BrutalLogiC]

Hi I want a cell to display the overall average of all cells which are either A or B.

Column A = cells will be either A, B, C, D etc..
Column B = values

I thought maybe it will be but not sure..
=AVERAGEIFS(B1:B100,A1:A100,"A",A1:A100,"B")

 

[Marcelo Branco]

Try

=SUM(SUMIF(A1:A100,{"A";"B"},B1:B100))/SUM(COUNTIF(A1:A100,{"A";"B"}))

M.

 

[gaz_chops]

Or

=AVERAGE(IF($A$2:$A$20={"A","B"},B2:B20))

Enter as an array, Ctrl Shift & Enter