The required diameter of circle is 6.69 inches.
Circumference of a circle = 21.
Diameter has to be determine.
Diameter is longest chord of the circle contains the center of the circle.
Here,
Circumference of circle = πd
21 = 3.14d
d = 21/3.14
d = 6.69
Thus , the required diameter of circle is 6.69 inches.
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