SUM Function

[Guest]

I am trying to do a sum across rows in which the operand is determined by
taking the value in the cell and subtracting it from said value times a
percentage.

For example:
(T3-(T3*I3)) + (T4-(T4*I4)) + (T5-(T5*I5)) + ...

I'd like to avoid the manual function shown above and instead go with
something like:

SUM((T3-(T3*I3))T9-(T9*I9)))

The SUM function does not appear to support this. Is there a way to
accomplish this without resorting to a manual function?

Thanks,

Rick

 

[Guest]

=SUM(T3-(T3*I3))+SUM(T9-(T9*I9))

Dave

 

[RichardSchollar]

Hi Rick

You can use SUM, but you need to array-enter it:

=SUM(T3:T9*(1-I3:I9))

which must be confirmed with Ctrl+Shift+Enter (not just enter). If it
has worked, Excel will surround the formula with curly braces ({}).

Hope this helps!

Richard

 

[Lori]

Try one of these:

=SUMPRODUCT(T3:T9-(T3:T9*I3:I9))
=SUMPRODUCT(T3:T9,1-I3:I9)

 

[David Biddulph]

In your formula, Dave, the SUM() functions are doing nothing, and more
significantly the OP doesn't just want to add the row 3 and row 9 values, he
wants the rows between included.