Answer:
(A) 22π mi, 69.08 mi
Explanation:
Exact circumference:
Normally, the formula for circumference is C = πd, where
- C is the circumference,
- and d is the diameter
Because the diameter is 2 * the radius (r), we can rewrite circumference in terms of r using the formula C = 2rπ
Since the radius is 11 mi, we plug this in for r in the formula and simplify:
C = 2(11)π
C = 22π
Thus, the exact circumference of the circle is 22π mi.
Approximate circumference:
We can still use the equation C = 2rπ, but use 3.14 for π and simplify:
C = 2(11) * 3.14
C = 22 * 3.14
C = 69.08
Thus, the approximate circumference of the circle is 69.08 mi.