Sum of a Look up Value

[Jafferi]

A B C
=================
134939 9 134939
134939 5
134939 5
135661 2
135661 90

I tried =LOOKUP(a:a,C,(SUM(B:B))) does not give me the total sum of 134939.
I need help to total up the value of B for the data in C.

 

[T. Valko]

Try this:

=SUMIF(A$1:A$5,C1,B$1:B$5)