Numbers: How to make a sum product of 2 columns numbers of which only those with checkboxes checked in a 3rd column respectively? Say, sumproduct(A, B)=a1*b1 + a2*b2 + a3*b3, now I have many columns C, D,..., e.g. c1 checked, c2 unchecked, c3 checked; d1 unchecked, d2 checked, d3 checked;

Now I need a formulae which I want to put in a cell of each of column C, D... to compute a conditional sum product to get a1*b1 + a3*b3 and a2*b2 + a3*b3 respectively.

This can be used in my nutrition calculation table of daily intake.

Thanks a lot.
You can add an additional column D, where D1 to D3 would contain:

IF(C1,1,0)
IF(C2,1,0)
IF(C3,1,0)


This would print a 1 if checked or a 0 if not checked, and you simply would need to add column D into your sumproduct:

a1*b1*c1 + a2*b2*c2 + a3*b3*c3