circumference of the circle? (Circumference 2*pi *r)

then R = r+ r/2

= 3r/2 = 1.5r

thus, increase in circumference = 2 pi r = 2 x pi x 1.5 r

= 3 pi r.

Thus initial c = 2 pi r, final c = 3 pi r.

thus increase percent = change in c/ initial c x 100 = 1/2 x 100 = 50 percent.

Thus, the circumference will also increase by 50 %