Answer:
exact arc length = 21pi
approximate arc length (using calculator) = 65.9734457253857
approximate arc length (using 3.14 for pi) = 65.94
units are in feet
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Work Shown:
L = (x/360)*2*pi*r
L = (315/360)*2*pi*12
L = 21pi = exact arc length in terms of pi
If you use your calculator's stored version of pi, then L is approximately
L = 21pi
L = 65.9734457253857
Or if you end up using pi = 3.14, then
L = 21*pi
L = 21*3.14
L = 65.94
Fairly close to the other approximation though a bit off because pi = 3.14 is just a rough approximation.
