This worksheet is designed to help learners practise the skill of working backwards to find a radius or diameter of a circle when the area or circumference is given.

Section A begins with some fill-the-gap missing number questions where learners will be finding a missing diameter or radius from a circumference calculation.

Section B then gives some circles with known circumferences, and learners need to find the missing diameter or radius.

Section C then provides some more fill-the-gap questions linked to the area formula before section D presents some circles with known areas for learners to find the missing radius or diameter.

Section E then give some semicircles and sectors with a known area for learners to find a missing value.

The worksheet ends with section F providing some problem-solving questions.