Give the exact answer in terms of Pi and then calculate the required approximate answer using Pi .

Question

The diameter of a CD is 3 in. How far does a point on the rim os this CD travel when the CD makes two-thirds of a complete revolution? ( Round your answer to two decimal places).

Answer 1

two - thirds of the circumference =

 

2/3 * pi * diameter = 2/3 * pi * 3 = 2 * pi = 2 * 22/7 = 44/7 = 6 and 2/7 inches  

                                                       or roughly 6 and 5/16 inches

 

As requested, 6.28 in correct to two digits.

The exact answer highlighted in bold above