4. The radius of a circle is increased, sothat its circumference incre

1.	4. The radius of a circle is increased, sothat its circumference increases by15%. The area of the circle will increase[CDS 2017 01by/h)22 25%
Answer» Circumference of circle = 2πr Area of circle =πr2 New circumference after increase in radius = 1.15 × 2πR Since circumference∝ radius of circle, radius increases by 15% R = 1.15r New Area =πR2= π(1.15r)2= 1.3225πr2 So, area is increased by 32.25%. hit like if you find it useful

4. The radius of a circle is increased, sothat its circumference increases by15%. The area of the circle will increase[CDS 2017 01by/h)22 25%

Answer»

Circumference of circle = 2πr

Area of circle =πr2

New circumference after increase in radius = 1.15 × 2πR

Since circumference∝ radius of circle, radius increases by 15%

R = 1.15r

New Area =πR2= π(1.15r)2= 1.3225πr2

So, area is increased by 32.25%.

hit like if you find it useful