Ingeometry, the word concentric denotes a common center. Just like 3 points are collinear if they are on the same line, two circles are concentric if they share a common center.
This is a very neat puzzle as it tests our understanding of elementary geometry
Here’s a hint: unleash your hidden drawing skills …
I recommend you pause the article, grab your pen and paper, and give this a go. When you are ready, keep reading for the solution!