Question

Sean used candle molds, as shown, to make candles that were perfect cylinders and spheres:

What is the approximate difference in the amount of wax needed to make a candle from each of these molds? Use π = 3.14.

18.0 cubic inches
28.26 cubic inches
37.0 cubic inches
56.52 cubic inches

Answer 1

We calculate for the volumes of each of the wax needed for the candles through the equations presented below.

For cylinder:
V = πr²h
where V is volume, r is radius and h is height.

Substituting the known values,

V = (3.14)(3 in)²(6 in)
V = 169.56 in³

For sphere:

V = 4πr³/3
Substituting the known values,
V = 4(3.14)(3 in)³ / 3 = 113.04 in³

The difference between the two volumes,

difference of volumes = 169.56 in³ - 113.04 in³
difference of volumes = 56.52 in³

Thus, the answer to this item is the last choice.