Woody wrote:
how do I copy a formula i.e. =K64-M65 into all cells in a row

If you want that the formula referers always to the same cells, you have to
use absolute references, i.e. you have to insert the formula in this way:

=$K$64-$M$65

the you can drag the cell with the formula...


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Hope I helped you.

Thanks in advance for your feedback.

Ciao

Franz Verga from Italy