=SUMPRODUCT(--(LEFT(A1:A7,1)={"A","B"}))

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mama no teeth

"JRD" wrote:

Please help, I'm stuck.

How can I count the number of cells containing certain words but avoid
counting the same cell twice.

E.g.

Column A
A
B
C A
B A
A B
B
A

How do I count the number of cells containing A added to the number of cells
that contain B without double counting those that contain A and B

The answer in the above example should be 6 (NOT 7)

Many thanks