Question

find the ratio between the circumference of two circles whose redi are in the ratio 2 is to 3​

Answer 1

Answer:

2:3

Step-by-step explanation:

ALWAYS REMEMBER THIS!! IT IS VERY USEFUL FOR ALL TYPE OF EXAMS RELATED TO MATHS AND IT SAVES A LOT OF TIME

"If the ratio of 2 radius of circle is x:y then the ratio of circumference for both circle is also x:y"

PROOF---->

Circumference of 1st circle = 2 x Pi x r1

Circumference of 2nd circle= 2 x pi x r2

Ratio= 2 x pi x r1 / 2 x pi x r2   = r1/r2

Thus, the answer will be 2:3

Please mark as Brainliest

Answer 2

★ Given:

The ratio between the radii of two circles is 2:3.

★ To Find:

The ratio between their circumferences.

★ Solution:

Let the radii of the two circles be 2x and 3x.

We know that the formula to find the circumference of a circle is 2πr.

Circle 1

Radius = 2x

Circumference = 2πr

= 2 x π x 2x

= 4x x π

Circle 2

Radius = 3x

Circumference = 2πr

= 2 x π x 3x

= 6x x π

Ratio of their circumferences:

$\sf{\dfrac{4x\times\pi}{6x\times\pi}}$

Cancelling the x and π, we are left with:

$\sf{=\dfrac{4}{6}}$

$\sf{=\dfrac{2}{3}}$

= 2:3

Hence the ratio between the circumferences of the circles is also

2:3

Important Area Formulae:

→ Area of a square = a²

→ Area of a rectangle = lb

→ Area of a circle = 2πr

→ Area of a right angled triangle/a triangle with the height provided = 1/2bh

→ Area of a parallelogram = bh

→ Area of a rhombus = bh / 1/2d1d2