The circumference of the circle C subscript 1 is 9 cm and the circumference of C subscript is 2 pi cm. what is the value of the ratio of the areas of C subscript 1 to C subscript 2
+37170 c1 pi x d = 9 so d= 9/pi radius = 9/(2pi) Area = pi r^2 pi (9/(2pi))^2 = pi (81/(4pi^2) =81/(4pi)
c2 d=2pi/pi =2 radius =1 Area = pi r^2 = pi
ratio area c1/c2 = 81/(4pi) / pi = 81 / (4pi^2)
Are you sure the first circle c1 circumference was not 9pi ?? If it was, the ratio works out to 20.25 (the same as 9^2 / 2^2)
