Question

The ratio of circumference of any circle to its diameter is

Answer 1

it is equal to pie.(π).

ratio=2πr/d ....(where d is the diameter)

& we know...d is equal to two times the radius.

Therefore

ratio=2πr/2r=π.

Answer 2

$the \: \: circumference \: \: of \: \: the \: \: circle \: \: is \\ \: \: 2\pi \: r$

$the \: \: diameter \: of \: circle \: \: is \\ 2r$

$So\:ratio\: is \:equal \:to\: 2\pi r ÷2r=\pi$