# The question is below?

##
# mutually tangent spheres of radius 1 rest on a horizontal plane. A sphere of radius 2 rests on them. What is the distance from the plane to the top of larger sphere?

# mutually tangent spheres of radius 1 rest on a horizontal plane. A sphere of radius 2 rests on them. What is the distance from the plane to the top of larger sphere?

##### 1 Answer

The distance is

#### Explanation:

Let the radiuses of the mutually tangent spheres be

respectively

Let

Recall the distance formula:

Thus,

Since

Since the radius of the sphere is 2,

height