wiz-icon
MyQuestionIcon
MyQuestionIcon
1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

The radii of the two circles are 19 cm and 9 cm respectively. Find the radius of the circle which has circumference equal to the sum of the circumferences of the two circles.

Open in App
Solution

Let r1 and C1 be the radius and circumference, respectively of 1st circle and r2 and C2 be the radius and circumference, respectively of 2nd circle.
Let r3 and C3 be the radius and circumference, respectively of the required circle.

r1=19 cm ...Given
C1=2πr1
C1=2π×19=38π cm ...(1)

r2=9 cm ...Given
C2=2πr2
C2=2π×9=18π cm ...(2)

C3=C1+C2 ....Given

C3=38π+18π ....From (1) and (2)

C3=56π cm

2πr3=56π

r3=28 cm

The radius of the required circle is 28 cm

flag
Suggest Corrections
thumbs-up
1
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Circumference of Circle
MATHEMATICS
Watch in App
Join BYJU'S Learning Program
CrossIcon