Hi all

E1:20

A1:1 B1:=sum(A1*E1)*0.15
A2:2 B2:=sum(A2*E1)*0.15
A3:3 B3
A4:4 B4
A5:5 B5
...
..

I will like to copy the formula in B1 down to B50 and more in future but how
do I ensure that only A1 will change as I copy downwards but the E1 will
remain as a fixed reference cell in the formula?

I will change the figure in cell E1 as and when needed.
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