Question

The circumference of the inner circle is 66 ft. The distance between the inner circle and the outer circle is 3 ft. By how many feet is the circumference of the outer circle greater than the circumference of the inner​ circle? Use ²²⁄₇ for π.

Thanks in advance!

Answer 1

`6\pi = \boxed{18.9ft}`

Answer 2

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Answer:

18 6/7 ft

Explanation:

The circumference is given by the formula ...

C = 2πr

The circumference of the larger circle is then ...

C' = 2π(r+3) = 2πr +6π

The difference in circumference is ...

C' -C = (2πr +6π) -(2πr) = 6π

For the given value of π, the difference in circumference is ...

(22/7)(6 ft) = 132/7 ft = 18 6/7 ft

The circumference of the outer circle is greater by 18 6/7 ft.