Find difference between two columns of data

[BWMagee]

In column A I have the following numbers:
1, 4, 7

In column B I have the following numbers:
3, 1, 9

I want to find the average difference between these numbers in the following fashion:
=ABS(A-B)

Eg.
ABS(1-3) = 2
ABS(4-1) = 3
ABS(7-9)= 2

Then:
AVERAGE(2,3,2) = 2.33

However if I were to do this:
=ABS(AVERAGE(A:A)-AVERAGE(B:B))

The result given would be 0.333, which is not what I want.

Is there a formula that will achieve the 2.33 answer that can be used in one cell, not needing to put the ABS(A-B) in a separate column? I ask, because I will need to use this on a much larger data set.
If not, I will create the helper column. Thanks.

 

[kevin9999]

Book1
	A	B
1	1	3
2	4	1
3	7	9
4
5	2.33
Sheet3

Cell Formulas
Range	Formula
A5	A5	=AVERAGE(ABS(A1:A3-B1:B3))

 

[BWMagee]

Thanks very much, it works, but has to be entered as an array formula, ctrl + shift + enter, to enclose with curly brackets { }

 

[kevin9999]

Happy to help & thanks for the feedback
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