First, you need to define the problem so people can understand it.

Your first collection of A, B, C adds up to 10,000, but you want 8000 as an
answer. Your second collection adds up to 7,000 which is also the answer you
want.

So tell us, what is the total you want? A plus C and ignore all B's? What
other rules are required to be followed in the 'lot of collection's you
have? Is it always the previous three numbers?

Regards,
Fred.

"kingkingking" wrote in message
...
So how excatly i am going to do?
"mvk"
...
The easiest way to do this would be to have categories column, and then
use a sumif function to sum the categories


"kingkingking" wrote in message
...
Can any body think of a formula if i want to sum up each collection as
follow, because i have a lot of collection cell i have to calculate.
A 5000
B 2000
C 3000
Collection : 8000

D 1000
E 2000
F 4000
Collection 7000

G
H
I
Collection