Aimee packs ice cream into an ice cream cone. She then puts a perfect hemisphere of ice cream on top of the cone that has a volume of 4 in.3 The diameter of the ice cream cone is equal to its height. What is the total volume of ice cream in and on top of the cone? Use the relationship between the formulas for the volumes of cones and spheres to help solve this problem. Show your work and explain your reasoning in easy words in a paragraph

1 answer

To solve this problem, we can use the relationship between the formulas for the volumes of cones and spheres. The volume of a cone is given by the formula V_cone = (1/3) * pi * r^2 * h, where r is the radius of the cone and h is the height of the cone. The volume of a sphere is given by the formula V_sphere = (4/3) * pi * r^3, where r is the radius of the sphere.

In this problem, we are given that the diameter of the ice cream cone is equal to its height. This means that the radius of the cone is half of its height. Let's denote the radius of the cone as r_cone and the height of the cone as h_cone.

Since the diameter of the cone is equal to its height, we have r_cone = h_cone/2.

We are also given that the volume of the hemisphere of ice cream on top of the cone is 4 in.3. The volume of a hemisphere is half the volume of a sphere, so we can write this as (1/2) * V_sphere = 4.

Let's solve the equation (1/2) * V_sphere = 4 for V_sphere:

(1/2) * V_sphere = 4
V_sphere = 8

Now, using the relationship between the formulas for the volumes of cones and spheres, we can write the volume of the cone as (1/3) * pi * r_cone^2 * h_cone.

Substituting r_cone = h_cone/2 into the formula for the volume of the cone, we get:

V_cone = (1/3) * pi * (h_cone/2)^2 * h_cone
= (1/3) * pi * (h_cone^3)/4

The total volume of ice cream in and on top of the cone is the sum of the volumes of the cone and the hemisphere. Therefore:

Total volume = V_cone + V_sphere
= (1/3) * pi * (h_cone^3)/4 + 8

And that's the final answer!