Question

A 3-gallon tub of ice cream yields about 90 scoops of ice cream. There are roughly 3785 cubic centimeters in 1 gallon. Determine the radius of each scoop, to the nearest tenth.

Answer 1

The radius of the scoop is r = 3.1 cm

Explanation:

Since 3 gallons yields 90 scoops, and 1 gallon = 3785 cm³.

3 gallons = 3 × 3785 cm³ = 11355 cm³

So we have 11355 cm³ in 3 gallons which is also the volume of 90 scoops.

Since 90 scoops = 11355 cm³, then

1 scoop = 11355 cm³/90 = 126.2 cm³

Now, if each scoop is a sphere, the volume is given by V = 4πr³/3 where r is the radius of the scoop. Since we need to find the radius of the scoop, r, making r subject of the formula, we have

r = ∛(3V/4π)

Substituting V = 126.2 cm³, we have

r = ∛(3× 126.2 cm³/4π)

= ∛(378.6 cm³/12.57)

= ∛30.13 cm³

= 3.1 cm

So, the radius of the scoop is r = 3.1 cm