This worksheet scaffolds the thinking processes behind finding the diameter and radius of a circle from the circumference. So the red section has the same difficulty questions but the thinking skills have been simplified.

It is differentiated like this:
Red - Lots of support, fewer questions
Amber - Less support, more questions
Green - No support, lots of questions.
Extension - Worded/Problem Solving questions with support to help begin.

Also included are sheets with 2 reds and 2 ambers so they can be printed back to back, with the green and extension projected on the board.