Sector Area

Circles: Fractions to Degrees and Back

A prerequisite for our Circles Unit

Multiple Choice

How many 1 degree turns are in a full circle?

• 500

• 1000

• 360

• 15

360°

We've learned that circles are divided into 360 equal pieces called degrees.

In this lesson, we're going to practice converting fractions of a circle to the equivalent degrees and back again!

Multiple Choice

What is the measure of the shaded part of the circle?

• 180 degrees

• 90 degrees

• 360 degrees

• 270 degrees

Multiple Choice

What is the measure of the shaded part of the circle?

• 180 degrees

• 90 degrees

• 360 degrees

• 40 degrees

Multiple Choice

How many degrees are in 1 part of a circle that is cut into 4 parts?

• 180

• 75

• 90

• 360

Multiple Choice

If an angle is a right angle, how many 1-degree turns does the angle have?

• 360
• 1
• 90
• 75

Multiple Choice

How many degrees are in the shaded part of this circle?

• 72

• 360

• 90

• 45

Multiple Choice

The circle is split up by 8 congruent angles. Which statement is true about the circle?

• Each angle would turn through 8 1° angles

• Each angle measures 90 degrees

• Each angle forms 1/8 of the circle

• Each angle measures 360 degrees

Multiple Choice

In a circle, 253° is the same as:

• $$\frac{253}{360}$$  

• $$\frac{18}{26}$$  

• $$\frac{54}{87}$$  

• $$\frac{2}{3}$$  

Multiple Choice

In a circle, 300° is the same as:

• $$\frac{2}{3}$$  

• $$\frac{15}{30}$$  

• $$\frac{4}{5}$$  

• $$\frac{5}{6}$$  

Area of a Sector

Ex 1:

Multiple Choice

Find the area of a sector with a radius of 9ft and an angle measure of

$$132\degree$$  

• $$10.37\ ft^2$$  

• $$93.31\ ft^2$$  

• $$29.7\ ft^2$$  

• $$85\ ft^2$$  

Fill in the Blanks

Find the area of the sector shown. Round to the nearest hundredth

Multiple Choice

Find the area of the shaded sector of circle O. The radius is 6 inches and the central angle is 100°. Express answer as an exact value

• 5π/3

• 10π/3

• 10π

• 40π

Multiple Choice

What is the area of the shaded region? Express answer as an exact value

• 8π/3

• 2π/3

• 32π/3

• 4π/3

Multiple Choice

The windshield wiper of a car rotates through an angle of measure 150°, as shown.

The shaded section of the diagram represents the area cleared by the 10-inch blade of the windshield wiper as it moves from one side to the other. The wiper is attached to a pivot that is 2 inches from the base of the blade.

Approximately what is the area cleared by the blade of the windshield wiper?

• 125 in²

• 183 in²

• 367 in²

• 790 in²

Poll

I can use the formula for finding the area of a sector.

• I need help

• I almost got it

• I got it

• I got it and I can teach someone else