Circles (AQA GCSE Maths): Flashcards

Distance from centre to edge of circle

Distance across circle through centre

Distance around the edge of a circle

$d = 2r$

$C = \pi d$

$C = 2\pi r$

3.142

Only at the final step

$d = \frac{C}{\pi}$

$r = \frac{C}{2\pi}$