hi,

In worksheet 11, if the names are in column A and the on / off in column B

=IF(B1="on",INDIRECT(A1&"!A1"),0)
fill down

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isabelle

Le 2011-04-20 17:32, Domanda a écrit :
I have ten worksheets, named 1 to 10.
In worksheet 11 I have 10 cells, numbered 1 to 10, and for each of
them I write ON or OFF.
I know how to sum cell A1 in each worksheet, but I ignore how to have
the sum conditioned to the fact the worksheet is ON.
Something like:
If the worksheet is active/on, then you add cell A1 of that worksheet,
and check the remaining 9 worksheet. If the worksheet is OFF, you skip
it and do not consider in the sum.
Compared to the normal SUM.IF, the range to be checked is spread over
the 10 worksheet.

Hope it is clear
thanks in advance