What standing wave ratio results from connecting a 50-ohm feed line to a 200-ohm resistive load?

Standing Wave Ratio (SWR) for purely resistive loads can be easily calculated by finding the ratio of the load impedance to the feed line impedance. You always place the larger number in the numerator so the resulting ratio is 1 or greater. In this case, you divide the 200-ohm load by the 50-ohm feed line (200 / 50 = 4). Therefore, the SWR is exactly 4:1. Distractors with ratios less than 1 (like 1:4 or 1:2) are incorrect because SWR is conventionally expressed as a ratio of a larger number to 1. A perfectly matched system is 1:1, and any mismatch increases the first number.