Well, this is REALLY weird. If I put this formula in a brand new spreadsheet

=IF(AND(ISNUMBER(A1:A3)),SUM(A1:A3),"")

It returns "".

After entering a number in A1 - no change
After entering another nunber in A2 - no change
After entering another nunber in A3 - I get the sum - as the formula would
suggest

Now if I select either A1 or A2 and Clear All, the sum remains but changes
to reflect the remaining values. This doesn't look right because of the AND()

Now I enter new values in A1 & A2 the sum updates

But, if I Clear All on A3 only, the sum disappears.

SO....THIS DOESN'T BEHAVE CONSISTENTLY, Right?




" wrote:

Problem:

When I enter the following equation into a cell with a blank in cell
CH12 or CH13 I get the correct answer (the sum of the cells with
numbers in them) but when there is a blank in cell CH14 I get an
incorrect answer (in the form of a clank cell).

=IF(AND(ISNUMBER(CH12:CH14)),SUM(CH12:CH14),"")

Does anyone have any suggestions?

Thanks,
Elaine