Question

The sum of the radii of two circles is 7cm. And the difference of their circumferences is 8cm. Find the circumference of the circles

Answer 1

let a and b are the radii of 2 circles respectively

a+b=7----eq 1

2pi(a-b)=8 ----equation 2

take pi=22/7 and substitute in eq 2

a-b=1.27

solving eq 1 and e1 3 , we will get the values of a=4.135, b=2.865

Answer 2

Circumference of the circle is 18 cm.