Question

The ratio of circumference of a circle to its diameter is always equal to .

• A. $\pi$
• B. $\frac{\pi }{d}$
• C. 3.366
• D. d

Answer 1

The correct option is A $\pi$

The ratio of the circumference of a circle to its diameter remains constant no matter what the radius is.
Let the radius of a circle be $r$
Circumference of the circle $=2\pi r$
Diameter of the circle $=2r$
$\frac{\text{Circumference of the circle}}{\text{Diameter of the circle}}=\frac{2\pi r}{2r}=\pi .$