Sector area worksheets

A sector is a slice of a circle, and its area is that same fraction of the whole circle's area. These free printable worksheets keep to the slice alone.

Sector area
Sector area worksheet — Slice area only, π = 3.14, free printable with answer key

The answer key prints on a separate page.

What's on this sheet

The circle's area is πr², and the slice is that times the angle over 360. Writing the fraction of the turn down first is the habit worth building: 120 over 360 is a third, and a third of the circle is easier to picture — and easier to check — than a formula with two multiplications in it.

Why this sheet works

Every angle here divides 360 exactly and every answer lands on two decimal places, so nothing on the paper says round to the nearest tenth. π is 3.14 throughout, the same as every other circle sheet on the site.