Q11 of 31 Page 183

If the sum of circumferences of two circles of radii R1 and R2 is equal to the circumference of a circle of radius R, then which of the following choices is correct?

Given: The sum of circumferences of two circles of radii R1 and R2 is equal to the circumference of a circle of radius R.


We know that circumference of the circle = 2πr


⇒ 2πR1+2πR2 = 2πR


⇒ 2π (R1+R2) = R


⇒ R1+R2 = R

More from this chapter

All 31 →
8

In the given figure, AB is a diameter, AC = 6 cm, BC = 8 cm. Find the shaded region.

 9

Find the area of the shaded design in the figure, where ABCD is a square of side 10 cm and semicircles are drawn with each side of the square as diameter (use π = 3.14).

 10

In the given figure, radius of the semicircle is 7 cm. Find the area of the circle drawn inside the semicircle.

 12

The circumference of the incircle of a square of side 14 cm is—