Circles: radius, diameter, and touching circles

A circle is every point the same distance from the centre, so the radius is the fact everything else is built on. When circles touch, the distance between their centres is the sum of the radii - drawing that line is usually the move.

Your progress

Not started

2Not started
0Familiar
0Proficient
0Mastered

Saved in this browser only. No account, nothing sent anywhere.

Work through it

LearnWhat it is, how to spot it, a worked example, and where it goes wrong.
Practice — 3-point ladderNo problems written at this tier yet.Nothing written at this tier yet
Practice — 4-point ladder1 problem. Three in a row finishes it.0/3 in a row · 0/1 solved
Practice — 5-point ladder1 problem. Three in a row finishes it.0/3 in a row · 0/1 solved
Skill quizFinish every ladder that has problems first.Finish the ladders above first

Before and after

Needs first

GEO-01Perimeter and area of rectilinear shapes

Opens up

Nothing yet. No other skill in the Atlas lists this one as a prerequisite.

In official papers

No indexed official paper question has been tagged with GEO-07 yet. The index grows one paper at a time, and it records only question numbers, point values and our own skill tags — never the problems themselves.

See the papers indexed so far

Loading…