1. The problem statement, all variables and given/known data Given that the souce voltage = Vo, find the Current at resistor 4. 2. Relevant equations For resistors in series, I = constant For resistors in parallel V = constant 3. The attempt at a solution So I gather that since the block containing resistors 2-5 is in series with R1, then whatever current leaves R1 must enter that block as well. So at R1 we have: V1 = Vo = I1*R1 so that the current leaving R1 and entering the block is I1 = Vo/R1 Now I need to find out how much of that current diverges into R4. Here is what I am thinking: The amount of current entering R2 and R4 is weighted by one of two things, either the values of R2 and R4 OR the values of (R2 + R3) and (R4 +R5), that is the total resistances in each 'leg' of the block. I think it is the latter, but I am hoping someone can confirm. Any thoughts?