The radii of two circles are 8cm and 12cm. What is the ratio of their circumferences?

Answer 1

hey it is the ratio of their radii.
for ex let r1 and r2 b the radii.
then circumference of circle 1=2* pi*r1
similarly for circle 2 it is 2*pi*r2
ratio:2*pi*r1:2*pr*r2
cancelling the constant terms it is r1:r2.
note:
if it is area then it wud be :r1^2:r2^2
so ur answer wud be 8:12 or 2:3

Answer 2

Circumference of a c ircle = 2*pi*r
So the cirumference of the circle with radius 8 cm = 2*22/7*8
and the circumference of the circle with radius 12 cm = 2*22/7*12
Let the radius of 8cm circle be R1 and the other one be R2
Then there ratio is R1/R2
= (352/7) divided by ( 528/7 )
= (352/7) * (7/528)
= 352/528 ( as 7 will get cancelled due to multiplication sign )
= 1/2 ( when simplified )
Hence the ratio of the two circumferences is 1:2

That was a really easy one

Answer 3

circumference of a circle = 2∏r.
ratio of the two circles with radii 8cm and 12cm = 8:12 or simplified to 2:3..

Answer 4

The ratio will be 8:12 or 2:3. Remember that

Circumference = Pi x 2 x Radius

Hence, ratio will be 8:12 and NOT 64:144

Cheers

Answer 5

The Accountant is wrong!! He is confusing area with circumference. The correct answer is 12 to 8 or 3 to 2 as in the first response.

Answer 6

8/12=2/3

Answer 7

let radii are r1 and r2.
and c1 and c2 are their circumference respectively.
c1= 2*pi*r1
c2=2*pi*r2
therefore, clear from above values of c1 and c2 , the ratio of circumferences is the ratio of radii.
required ratio=8:12=2:3.

Answer 8

Be careful!! Remember that the circumference = Pi*(radius)*(radius)

So the circumferences have a ratio of 64 to 144, or simplified to 4:9

You're correct I was thinking area DON'T USE THIS ANSWER!!! even us math majors are wrong from time to time

Answer 9

8 to 12. Or in reduced form, 2 to 3.

Answer 10

8:12. In other words same as ratio of radii or ratio of diameters. Area is " pi*diameter" (and "pi" is constant)