If the circumference and area of a circle are numerically

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If the circumference and area of a circle are numerically equal, then the diameter is equal to :

We know that The area of circle = πr²

	πD²
	4

[where D : diameter of circle] and Circumference of circle = 2πr = πD
Now, according to question,

	πD²	= πD
	4

D² = 4D
D² – 4D = 0
⇒ D(D – 4) = 0 ⇒ D = 4