How to sum resistors in parallel and series?
It often helps to re-draw the circuit in a way that makes more sense to you - it may take several tries to see the "real" circuit arrangement.

When I re-draw your circuit, the first thing I do is arrange it so that electricity flows from left to right, as God intended.  :)







simulate this circuit &ndash; Schematic created using CircuitLab

Here we can see that R5 is simply between Vin and Ground, so has no effect on the rest of the circuit.  R4 and R3 form a voltage divider, which feeds another voltage divider consisting of R2 and R1.  If you had some values for the resistors and for Vin, it would be simple to calculate Vout.