The answer that goes in the blank is: 3
Note: The "pi" portion is already taken care of, so there's no need to enter it in the box.
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Step-by-step explanation:
The distance around the entire circle is found by the circumference formula
C = 2*pi*r
where r is the radius.
In this case, r = 27, so,
C = 2*pi*r
C = 2*pi*27
C = 2*27*pi
C = 54*pi
The full distance around the circle is exactly 54pi units
We only want a small portion of it. We only want 20/360 = 2/36 = 1/18 of that distance
So multiply (1/18) by 54pi and we get...
(1/18)*(54pi) = (54/18)*pi = 3pi
So the length along the curve from A to B (or vice versa) is exactly 3pi units.