How do you find the central angle of a pie chart for a section of the pie chart that represents 20% of the pie?

1 Answer
Feb 25, 2018

#20% " of " 360° = 72°#

Explanation:

In any sector, there are #3# parts to be considered:

the arc length,
the sector area
the sector angle

They all represent the SAME fraction of the whole circle.

The arc length is a fraction of the circumference
The sector area is a fraction of the whole area
The sector angle is a fraction of #360°#

If the sector is #20%# of the pie chart, then each of these parts is #20%# of the whole.

The sector angle is therefore:

#20% xx 360°#

#20/100 xx 360 =72°#