Micayla,
Nice name.
=Sum(E3:E11)/Sum(B3:B11) would work if you are looking for a single output
of the one column sum divided by the other.
OTOH if you want to divide each row and then sum the results, you could put
=E3/B3 in the C3 cell and copy down. Then sum the numbers in Column C.
If you are doing the latter, you can do it in one formula that looks like
the one you made, but when you build it, you need to convert it to an array
formula by hitting (not very hard) shift-control-enter.
it will end up looking like this {=SUM(D7:D23/E7:E23)} but you cannot enter
the brackets yourself, excel does it with the shift-control-enter key combo.
If you are dividing rows and then adding and want to do it in one shot
instead of using an extra column, see Create an array formula in Excel help,
the option you want is Calculate a single result.
Simply, you would build the formula just as you have it and put the cursor
in that cell and hit shift-control-enter and Excel knows it is an array
formula.
Be careful of which option you choose, because the column sums divdied do
not equal the sum of the individual divisions.
Hope this helps
SongBear


"Micayla Bergen" wrote:

> i have this formula =SUM(E3:E11/B3:B11), i want to divide the sum of the E
> column by the sum of the B column but am obviously missing something that
> will seem hideously obvious when pointed out
> thanks