Question

the diameter of the circle whose ares is equal to the sum of the two circle of radii 40cm and 9cm is?

Answer 1

let the radius of circle be r
then,A.T.G.C.
pi x r2= pi(40 ^2 + 9 ^2)
r2=400+81
r2=4081
r=41
d=82
________________________________________________________
____________________________________________thanks_______

Answer 2

Area of circle with radius 40 cm =πr² = 40²π= 1600π cm²

Area of circle with radius 9 cm =πr² = 9²π = 81π cm²

Sum = 1600 + 81 = 1681π cm²

Now area of required circle = 1681 π cm²
πr² = 1681π
r² = 1681
r = 41 cm

Diameter= 2r = 2 x41 = 82 cm

Your answer is 82 cm

Hope this Helps!!