If the circumference of a circle is 37" how much does it decrease if I decrease the radius by 1/2"?

Question

If my husband's waist size is 37", and a plastic surgeon says he can use a method to remove 1/2 INCH of fat from an area, how much will that decrease is waist size?  Or, if the circumference of a circle is 37" how much does it decrease if I decrease the radius by 1/2"?

Answer 1

Hi Ann,

 

the circumference of a circle C is given by

 

C = 2πr

 

where r is the radius. We can solve for the original radius using the given circumference:

 

r = C/(2π) = 37/(2π) = 5.89"

 

We want to consider a new radius that is 1/2" less, or r₂ = 5.39". What is the new radius C₂?

 

C₂ = 2πr₂ = 2π(5.39) = 33.87"