8.2 Circumference + Arc Length

If my radius is 10ft, what is my diameter?

• 20ft
• 5ft
• 31.4ft
• 62.8ft

what is the circumference of this circle ?

(in terms of pi)

Mathematical Equivalence

ON

A circular swimming pool is 21 feet in diameter.
How many feet around is the pool?

(in terms of pi)

Mathematical Equivalence

ON

Find the circumference of a circle with a radius of 12.5 mm .

• 37.68mm
• 18.84mm
• 78.5mm
• none of the above

What is the distance around a circle?

• Circumference
• Area
• Diameter
• Radius

Find the circumference of a circle with a diameter of 11 millimeters.

(in terms of pi)

Mathematical Equivalence

ON

What is the circumference of a circle whose radius is 4 inches?

• C = 4 inches

Which of the following units does NOT measure DISTANCE?

• feet

• inches

• degrees

• yards

What is the circumference of a circle whose diameter is 10 feet?

• C = 10 feet

• r = 14 yards

• r = 7 degrees

• r = 28 yards

• r = 7 yards