Circumference and Area of Circles Formula

The diameter of Joanne’s bicycle wheel is 18 inches. What is the circumference to the nearest tenth?

• 28.3 in

• 27 in

• 56.5 in

• 54 in

If the word problem is asking you to find the space inside the circle, which formula should you use?

• r = d/2

• d = 2r

• C = πd

• A = πr²

If the problem ask you to find the distance around a circle, which formula should you use?

• r = d/2

• d = 2r

• C = πd

• A = πr²

Which formula would you use to answer: Lauren's bicycle tire has a diameter of 20 inches. How many inches is one full revolution of the wheel?

What is the area of a circle that has a radius of 100 miles?

• 7,850 miles 

• 10,000 miles

• 31,400 miles

If a Circle has a radius of 3 cm and a diameter of 6cm , what is the circumference of the circle? 

• 9.42 cm

• 18.84 cm

If a circle has a circumference of 26.69 yards, what is it's diameter?

• 8.5 yards

• 83.8 yards

• 4.2 yards

• 17.6 yards

A circle has a radius of 150 mm. What is it's circumference? 

• 471 mm

• 942 mm

• 47.7 mm

What is the correct formula for the Area of a Circle? 

• A= π x d

• A = π x d²

• A= π x r²

Find the area for a circle with a diameter of 8 feet. 

• 200.96 feet 

• 25.12 feet 

• 12.56 feet 

• 50.24 feet