Hi there.
First of all, I guess you could continue updating your first post below ;)
Regarding to your problem, please, try:

=sum((B10:B20="s1")*(C10:C20<"x")*A10:A20) SHIFT + CTRL + ENTER

You should enter the above formula by pressing SHIFT + CTRL + ENTER (and not
just ENTER) since it is an array formula.

Regards,
Otávio

"tleehh" wrote:

colume a=value, colume b is notation with s1, s2, s3, and s4 according to the
type of values in colume a.
I want to add only values that was notated with s1 in colume b, but omitting
that was mark with "x" in colume c respectively.