2 Answers

Tharindu Pradeep · Answer 1 · 2019-10-24T03:01:45+0000

Answer:

The number by which the circumference is multiplied is:

2

We know that the circumference of the circle in terms of the radius r is given by:

$\text{Circumference}=2\pi r$

Now, if the radius is doubled.

i.e.

r'=2r

Hence, the circumference of the new circle is given by:

$\text{Circumference of new circle}=2\pi (2r)\\\\i.e.\\\\\text{Circumference of new circle}=2(2\pi r)$

i.e.

$\text{Circumference of new circle}=2* \text{Circumference of original circle}$

The constant by which the circumference is multiplied is: 2