applying formulas using cell references

[engrpetero]

Hi - I'm new here. I've looked over a few pages of posts but didn't find a topic I thought would address what I would like to do.

Suppose I have the numbers 1-10 in cells A1-A10 respectively

suppose in cell A12 I have a value x and in cell A13 I have a value y.

I would like to put a formula in cell A15 that sums up the values in cells Ax to Ay. For example, if the value in cell A12 is 4 and the value in cell A13 is 6, the result of the formula in cell A15 would be the sum of A4,A5,A6 = 15.

I have had no luck coming up with a formula that does this, or in searching for a formula that does this. A little help, please?

Thanks,
Peter

[martindwilson]

one way
=SUM(INDIRECT(ADDRESS(A12,1)&":"&ADDRESS(A13,1)))

[Cutter]

Use a combination of the SUM and INDIRECT functions

The formula in A15 would be:

=SUM(INDIRECT("A"&A12&":A"&A13))

[darkyam]

If the numbers are literally 1:10, or just consecutive integers, you can use =A13/2*(A13+1)-(A12-1)/2*A12 and not even really need the list.
Otherwise, I'd opt for the non-volatile Index function: =SUM(Index(A1:A10,A12):Index(A1:A10,A13))

[NBVC]

Try:

=Sum(Index(A1:A10,A12):Index(A1:A10,A13)

[martindwilson]

cutters is neater i went for overkill! then again NBVC is the best option as it doesnt involve indirect at all.
but it needs another )
=SUM(INDEX(A1:A10,A12):INDEX(A1:A10,A13))

[engrpetero]

Thank you all for the replies. They have done the trick (I implemented the last one) and by playing with each of them, I actually got to learn something (who knew, right?). Sincerely - thanks.