In column B under a heading 'letters' I have the numbers 1 2 3 1 in separate cell. In column C under a heading 'cost' I have the numbers 4 5 5 7 in sepate cells. I have named the ranges in columns B and C 'let' and 'cost'. I want a formula for the sum of all those cells in column C which have a '1' in column B. The answer should be 11. When I use an array formula with the curly brackets =SUM(IF(let="1",1,0)*cost) it works. If I put the numbber '1' into a separate cell, say E6 and replace "1" in the formula with E6 it doesn't work. Do you know why as this is what I need to do.

I'd appreciate any thoughts.

methody