Monday 4.29

What is the formula to calculate the circumference if you know the diameter of the circle?

• C = Pi * diameter

• C = 2 * Pi * radius

• C = radius * Pi

• C = diameter / Pi

If the diameter of a circle is 8 meters, what is the circumference using Pi as 3.14?

• 25.12 meters

• 50.24 meters

• 12.56 meters

• 100.48 meters

Did this question give you the radius or diameter? How do you know?

Answer explanation

Radius!! It starts in the center and touches ONE edge of the circle!

How do you calculate the circumference when given the radius?

• Add Pi to the radius

• Divide the diameter by Pi

• Multiply Pi by twice the radius

• Multiply Pi by the diameter

What does 'in terms of Pi' mean when calculating the circumference?

• Using an approximate value of Pi

• Leaving Pi as a symbol in the answer

• Ignoring Pi in calculations

• Multiplying Pi by 100

If the radius of a circle is 2.5 feet, what is the circumference in terms of Pi?

• 5 Pi feet

• 2.5 Pi feet

• 7.5 Pi feet

• 10 Pi feet