HELP I NEED IT NOW

Joel used candle molds, as shown, to make candles that were perfect cylinders and spheres: A cylindrical mold is shown, the radius of the top circular section of the cylinder is labeled 2 inches and the height of the cylinder is labeled as 3 inches. On the right side of this mold is a spherical mold. The radius of this spherical mold is labeled as 2 inches. What is the approximate difference in the amount of wax needed to make a candle from each of these molds? (Use π = 3.14.)

Respuesta :

DeanR

The volume of the cylinder is [tex] \pi r^2 h[/tex]. The volume of a sphere is [tex] \frac 4 3 \pi r^3 [/tex]. In our problem r is the same for both the cylinder and the sphere.


[tex] \pi r^2 h - \frac 4 3 \pi r^3 = \pi(2^2(3) - \frac 4 3 2^3) = \pi(12 - 32/3) = \frac 4 3 \pi \approx 4.19 \textrm{ cubic inches}[/tex]



Answer: 4.19 cubic inches