I need a formula to multiply f1:f4*a1:a4 then to total that number at the
end of the column in f5. Since there is also text in this column I just want
it to reconize the numbers.

Example of table below:

This is what my sad attempt looks like in cell f5:

=sum(f1*a1+f2*a2+f3*a3+f4*a4)

Which does work until I get to the text.

A B C D E F

10% 15.58 38.50 26.68 9.43 N/A

10% 13.51 36.03 24.85 6.41 3.34

4% 8.41 28.66 20.26 4.86 N/A

4% 3.67 1 3.86 15.75 9.89 9.20