Electronic – How to calculate a simple mixed parallel/series resistor circuit


I'm trying to understand how to calculate resistance in simple mixed parallel and series resister circuit. Below is a question from a worksheet I've been playing with to better understand the topic (Question 5 ->Figure 6).

Simple Resister Circuit

I can see the 220Ω and 100Ω resistors are in parallel, but I do not understand how to break out and calculate the 470Ω and 330Ω resistors.

The answer given is 80.54 Ω, but I cannot seem to reach this on my own.

How do I calculate the resistance between points A and B?

AllAboutCircuits.com – Series-Parallel DC Circuits Worksheet

Best Answer

Try re-drawing the schematic:


simulate this circuit – Schematic created using CircuitLab

Hopefully the solution will be obvious once you do so (comment/ask if it's not).