Question

find the diameter of a circle whose circumference is 63.8 m​

Answer 1

Answer:

Let the radius of the circle be r

Circumference

$= 2\pi r$

$= 2 \times 3.14 \times r = 63.8m \\ \\ \implies \: r = \frac{63.8}{2 \times 3.14} = 10.15m$

Diameter of circle

$= 2 \times r \\ \\ = 2 \times 10.15 = 20.3m$

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Additional information:-

•  a radius of a circle or sphere is any of the line segments from its center to its perimeter, and in more modern usage, it is also their length.
• the circumference is the perimeter of a circle or ellipse. That is, the circumference would be the arc length of the circle, as if it were opened up and straightened out to a line segment. 
• diameter of a circle is any straight line segment that passes through the center of the circle and whose endpoints lie on the circle. It can also be defined as the longest chord of the circle. Both definitions are also valid for the diameter of a sphere.

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