Multiple Database functions

[PompeyGirl]

Hello

I am working with a fairly large database and have been struggling to find a way to filter the data I need. It is quite complex as I want to find an average of data in column c (i.e consumption), which is...
1) equal to column d (i.e speed)
2) equal to column e (i.e model)
3) but (and this is the tricky bit) between a range of numbers for column f (i.e size).

The range I need in column f (size)is dependent on e (model). There is too many variants to do a simple string of nested functions. I tried to do a table and run a sumif i.e size on one axis and speed on the other, per model but the SUMIF doesnt seem to want to coexist with the AND function I need to bring in the range for size.

Anyone have an ideas how I can marry the SUMIF and the AND or perhaps can suggest a way to use a DFUNCTION.

Hopefully I have explained this well enough.

Thanks

[DonkeyOte]

I'm not sure I know exactly what you're trying to do -- if it's merely average C where those conditions are met you could use something like the below perhaps entered as an array using SHIFT + CTRL + ENTER:

=AVERAGE(IF(D1:D100=A1,IF(E1:E100=B1,IF(F1:F100>=A2,IF(F1:F100<=A3,C1:C100)))))

where A1 holds your speed criteria, B1 your model criteria, A2 & A3 your range min & max parameters.