Review what you know about the angles and arcs of circles below.
A circle is divided into nine congruent sectors. What is the measure of each central angle?
Recall that a whole circle is
In the diagram at right, what are
and if ?
Refer to the Math Notes in this lesson.
Notice the relationship between
at right, and units. What are and the length of ? What is the area of the smaller sector?
What portion of the circumference is
Use the same method as above to find the area of the smallest sector.