SOLUTION: The surface of a balloon varies directly as the square of its radius. The area is {{{314 cm^2}}} when the radius is 5 cm. What is the area when the radius is 10 cm?

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: The surface of a balloon varies directly as the square of its radius. The area is {{{314 cm^2}}} when the radius is 5 cm. What is the area when the radius is 10 cm?      Log On


   



Question 235351: The surface of a balloon varies directly as the square of its radius. The area is 314+cm%5E2 when the radius is 5 cm. What is the area when the radius is 10 cm?
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
The surface of a balloon varies directly as the square of its radius.
The area is 314 sq/cm when the radius is 5 cm.
What is the area when the radius is 10 cm?
:
If it varies directly as the square, when the radius is doubled the surface area is times 4
4 * 314 = 1256 sq/cm
;
:
You can check this using the surface area formula
S.A = 4*pi*10^2 = 1256.6