Question

Using the formula c=2r, find the circumference with diameter of 28inches. Round your answer to the nearest inch.

Answer 1

Radius is equal to 1/2 the diameter. The radius is 14 (28/2=14)

With your formula:

c=2*14

c=28

HOWEVER I believe you meant

c=2(pi)r

In which

c=2(pi)14

c=28(pi)

In this instance for pi we can use 3.14 since we will be rounding anyway, so

c=28*3.14

c=87.92

Rounded to be

c=88

Note:

If we didn’t round pi out to 3.14 we would have gotten 87.964594...