Question

The circumference of two circles are in the ratio 3 : 11.
a) Find the ratio of their radii.
b) Find the ratio of their areas.
c) If the radius of the smaller circle is doubled, what is the new ratio of their areas?
Pls write steps and send it quickly

Answer 1

Answer:

Let the radii of two circle be x and y

given ratio of circumference= 3: 11

$= \frac{2\pi \times x}{2\pi \times y}$

$= \frac{x}{y}$

1) ratio of radii = 3 : 11

$\frac{\pi \times {x}^{2} }{\pi \times {y}^{2} }$

${( \frac{x}{y} )}^{2} = {( \frac{3}{11} )}^{2}$

$\frac{ {x}^{2} }{ {y }^{2} } = \frac{9}{121}$

2) ratio of their areas = 9 : 121

3) Let the smaller circle radius be x

then the new radii be 2x

new ratio of the radii = 2x : y

= 2(x/y) = 2(3/11)

= 6/11

ratio of their areas =

$\frac{ {x}^{2} }{ {y}^{2} } = \frac{ {6}^{2} }{ {11}^{2} }$

ratio of their areas = 36: 121

hope it will helps you..

Mark Brainliest