Question

The radii of two circles are $25cm$ and $18cm$ . Find the radius of the circle which has circumference equal to the sum of circumferences of these two circles.

• A. $43cm$
• B. $45cm$
• C. $47cm$
• D. $59cm$

Answer 1

The correct option is A $43cm$

Given,
radii of the two circles=$25cm$ and $18cm$

Sum of circumference=$2\pi \left(25\right)+2\pi \left(18\right)$
=$86\pi$

Now,
Let the radius of the circle be $r$

Therefore,
$2\pi r=86\pi$

$=>r=\frac{86\times \frac{22}{7}}{2\times \frac{22}{7}}$

$=>r=43cm$