Answer: 14.28
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Step-by-step explanation:
The full circle has a circumference of
C = 2*pi*r
C = 2*3.14*4
C = 25.12
Divide this by four because we only want a quarter circle (and not the whole thing). Imagine cutting a pizza into four equal slices, and we only focus on one slice.
The curved portion of the slice is roughly 25.12/4 = 6.28 units long.
Add on the two straight line portions of the quarter circle to get 6.28+4+4 = 14.28
The straight line portions are the radius.
The answer of 14.28 is approximate because pi = 3.14 is approximate.