I have created a spread sheet that has a number of cells where the
figure shown is generated by a formula. After these figures are
generated I need to have them add themselves up.

the formula I used to generate the numbers is such as this:
=if(Q5="","",if(N5="","",if(K5="","",".5")))
These .5 values are percentages or 1/2%

I have a number of this type of formulas filling cells with .5. I want
to add up all these .5 figures so that I can then use the total to
multiply a gross value by to receive another value.

such as this:
..5
..5
..5
1.5 =.015 X 2000.00 = 30.00

I am finding that, because the cells are filled by formulas, they won't
add up.