Reteaching
Name
16-3
Understanding Angles and
Unit Angles
You can find the measure of an angle using fractions of a circle.
The angle is __16 of a circle.
What is the measure of this angle?
Divide to find the angle measure of __16 of a circle.
Remember, __16 means 1 of 6 equal parts, so divide by 6 to find the
angle measure.
Number of degrees
in whole circle
360° ÷ 6 = 60°
The measure of this angle is
60
Number of degrees in
the angle.
degrees.
For Exercise 1, show the work you do to find the measure of
the angle.
1. Use Structure A circle is divided into 9 equal parts.
What is the measure of this angle?
Write an equation using division to find the measure of the angle.
360
The measure of this angle is
9
÷
40
=
40
degrees.
2. Janie cut a round slice of watermelon into 5 equal pieces.
What is the angle of each piece? Use equivalent fractions.
The measure of this angle is
72
degrees.
3. Frank cut a pie into 10 equal slices. There are only 3 slices
left. What is the measure of the angle for the 3 slices that are
.
left?
108°
4. Maria cut a pizza into 8 equal slices. She put a slice of pizza
on 3 plates. What is the measure of the angle for the slices
.
that are left?
225°
3t
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