I'm not sure If I'm going mad or not...but a really simple equation in a
spreadsheet is not working...

My table is, eg, as below

A B C
1 5% 10
2 3% 12

in column C, i just want to get the total of a1 * b1, eg total = 0.5,
I was just assuming i could do @sum(a1*b1)......but that doesnt work

Any help please?

Thank you