Mack wants to calculate the circumference of a circle with a radius of 7 centimeters.

Question

write the letter representing each calculation under the category that correctly describes whether or not the calculation on its own results in the circumference of that circle.

Answer 1

The definition of π = (the circumference of a circle) / (the diameter of the circle)

 

   π = C/d

   C = πd

 

And, since the diameter (d) is twice the radius (r) [that is, d=2r],

  C = π(2r) = 2πr

 

The values 3.14 and 22/7 are rough approximations for π.

 

If r=7, then C = 2*(22/7)(7) = 44 cm.