formula to lookup & sum totals, given a start inv.# & finish inv.#

[Guest]

I have a worksheet containing the total of each invoice & then that gets
divided by two and placed into two seperate columns. I would like to retrieve
the total of a given number of invoices by entering a start inv.# & a finish
inv.# on a different sheet. Can anyone help me?

 

[Ardus Petus]

Say in Sheet2 start inv# is in A1 and finish inv# in B1;
Say in Sheet1, inv# is in column A and inv. amount in column B

In Sheet2, enter:
=SUMPRODUCT((Sheet1:A1:A1000>=A1)*(Sheet1:A1:A1000<=B1),Sheet1!B1:B1000)

HTH

 

[Guest]

Thank you very much Ardus Petus, I have been trying to work this out for
myself a long time and always seemed to go round in circles. Works perfectly,
thanks again.
Learning the hard way