Arc Length

If the circumference of a circle is 10 ft, then the arc length of a semicircle of this circle must be:

Hint:   $\frac{arc\ length}{circumference}=\frac{arc\ measure}{360\degree}$  

• 10 feet

• 5 feet

• 20 feet

• 180 degrees

• insufficient information

If the circumference of a circle is 50 ft, then the arc length of a semicircle of this circle must be:

Hint:   $\frac{arc\ length}{circumference}=\frac{arc\ measure}{360\degree}$  

• 50 feet

• 100 feet

• 25 feet

• 180 degrees

• insufficient information

If the circumference of a circle is 12 ft, then the arc length of a minor arc of the circle which measures 90 degrees must be:

Hint:   $\frac{arc\ length}{circumference}=\frac{arc\ measure}{360\degree}$  

• 12 feet

• 48 feet

• 6 feet

• 3 feet

• insufficient information

If the circumference of a circle is 4 feet, then the arc length of an arc measuring 90 degrees must be:

Hint:   $\frac{arc\ length}{circumference}=\frac{arc\ measure}{360\degree}$  

• 4 feet

• 360 feet

• 16 feet

• 1 foot

• insufficient information

If a minor arc measuring 120 degrees has an arc length of 5 feet, then the circumference of the circle containing that arc must be:

Hint:   $\frac{arc\ length}{circumference}=\frac{arc\ measure}{360\degree}$  

This equation can be solved for circumference such that:
 $circumference=\frac{arc\ length\cdot360\degree}{arc\ measure}$  

• 15 feet

•  $\frac{5}{3}$  feet

• 600 feet

•  $\frac{5}{120}$  feet

• insufficient information

If a major arc has an arc length of 12 feet and the circle containing that major arc has a circumference of 18 feet, then the measure of that major arc must be:

Hint:   $\frac{arc\ length}{circumference}=\frac{arc\ measure}{360\degree}$ .

This equation can be solved for arc measure such that:
 $arc\ measure=\frac{arc\ length\cdot360\degree}{circumference}$  

• 120 degrees

• 216 degrees

• 240 degrees

• 540 degrees

• insufficient information

If a minor arc measuring 60 degrees has an arc length of 4 feet, then the circumference of the circle containing that minor arc must be:

Hint:   $circumference=\frac{arc\ length\cdot360\degree}{arc\ measure}$  

• 15 feet

• 24 feet

• 36 feet

• 1.5 feet

• insufficient information

If a major arc has an arc length of 6 feet and the circumference of the circle containing that major arc is 8 feet, then the measure of the major arc must be:

Hint:   $arc\ measure=\frac{arc\ length\cdot360\degree}{circumference}$  

• 120 degrees

• 240 degrees

• 270 degrees

• 300 degrees

• insufficient information