Measurements of Arc Length in Circles

Measurements of Arc Length in Circles

Practice Reinforcement

Arcs: Part of a Circle

Multiple Choice

Which proportion set up correctly for the figure?

• $$\frac{arc\ length}{8\pi}=\frac{225\degree}{360\degree}$$

• $$\frac{arc\ length}{4\pi}=\frac{225\degree}{360\degree}$$

• $$\frac{arc\ length}{16\pi}=\frac{225\degree}{360\degree}$$

• $$\frac{arc\ length}{8\pi}=\frac{360\degree}{225\degree}$$

Multiple Choice

Which proportion is set up correctly for the figure?

• $$\frac{arc\ length}{8\pi}=\frac{180\degree}{360\degree}$$

• $$\frac{arc\ length}{4\pi}=\frac{180\degree}{360\degree}$$

• $$\frac{arc\ length}{16\pi}=\frac{180\degree}{360\degree}$$

• $$\frac{arc\ length}{360\degree}=\frac{4\pi}{180\degree}$$

Multiple Choice

The radius of a circle is 4 feet. What is the EXACT length of a 

$$225\degree$$  arc?

• 10 pi

• 225

• 2.5 pi

• 5 pi

​arc length=5pi

(in calculator you can type in the numbers and then add pi to your answer)​

​EXACT length left in terms of pi

​Set Up your proportion:

​Finding EXACT Length of Arc

Some text here about the topic of discussion

Multiple Choice

When the dog is outside she is tied to a stake in the center of a circular area of radius 24 feet. The angle between her dog house and her favorite hydrant is 165 degrees. What is the length of the arc from her dog house to the hydrant, following minor arc DG, to the nearest foot.

• 40

• 35

• 55

• 69

​When finding arc length that isn't in terms of pi...

Substitute ​3.14 for the pi symbol into your proportion or use the pi key on the calculator. You will more than likely get a decimal answer that you will need to round according to the specifications of the problem.

Geometry​

Arc Length​

Multiple Choice

what is the arc length

• 5.23
• 103
• 33.33
• 50

Multiple Choice

The arc length is 7cm

• True

• False it's 6.8cm

• False it's 7.4 cm

Multiple Choice

If an exact arc length is

$$\frac{4\pi}{7}$$  , approximate the length to the nearest hundedth. 

• 12.56

• 1.80

• 1.74

• 1.71

Multiple Choice

The radius of a circle is 7 feet. What is the approximate length of an 85 degree arc?

• 3.31 feet

• 14.83 feet

• 5.19 feet

• 10.39 feet

Fill in the Blanks

A circle has a radius of 3. A central angle is created with a measure of 40 degrees. Find the length of the arc created by this central angle to two decimal places.

Multiple Choice

Find the arc length.  Leave your answer in terms of π.

• 7/4π
• 7/2π
• 1/8π
• 45π

Fill in the Blanks

Find the EXACT length of a 60 degree arc that is in a circle with a radius of 6 feet. 

(type pi instead of using symbol

$\pi$  )

Fill in the Blanks

What is the EXACT length of the 90 degree arc in the figure?

(Type in pi instead of symbol)