Question

Find the diameter of the circle, which has circumference equal to the sum of the circumference of two circles with radii $7cm$ and $14cm$ ?

Answer 1

Let radius of circle be $r$ cm

$2\ast \frac{22}{7}\ast r=\frac{7\ast 7}{2\ast 22}+\frac{14\ast 7}{2\ast 22}$

$44\ast 7\ast r=\frac{7}{2}\ast 22\ast (7+14)$

$r=7+14=33$