All Intermediate Geometry Resources
Example Questions
Example Question #59 : Cylinders
A cylinder is cut in half and placed on top of a rectangular prism as shown by the figure below.
Find the volume of the figure.
In order to find the volume of the figure, we will first need to find the volumes of the rectangular prism and the half cylinder.
From the figure, you should notice that the length of the prism is also the diameter of the half cylinder. Thus, half the length of the prism will also be the radius of the half cylinder. Also, notice that the width of the prism will be the height of the cylinder.
For the given cylinder then, find the radius.
Then, recall how to find the volume of a cylinder:
, where is the radius and is the height.
Divide the volume by to find the volume of the half cylinder.
Next, recall how to find the volume of a rectangular prism.
Plug in the given values to find the volume of the rectangular prism.
To find the volume of the figure, add the volume of the half cylinder and the volume of the rectangular prism together.
Remember to round to places after the decimal.
Example Question #60 : Cylinders
The above diagram shows a sphere inscribed inside a cylinder.
The sphere has a volume of 100. Give the volume of the cylinder.
Let be the radius of the sphere. Then the radius of the base of the cylinder is also , and the height of the cylinder is .
The volume of the cylinder is
,
which, after substituting, is
The volume of the sphere is
Therefore, the ratio of the former to the latter is
and
That is, the volume of the cylinder is times that of the sphere, so the volume of the cylinder is
.
Example Question #61 : Cylinders
During a snow storm, of snow was collected. If the snow were put in a circular lot that had a radius of , how high would the snow on the lot be?
Since we are putting the snow on a circular base, we are dealing with a cylinder. Notice that the radius of the cylinder and the volume of the cylinder are already given to you.
Recall how to find the volume of a cylinder:
Rearrange the equation to solve for the height:
Plug in the given volume and radius:
The height is between and meter.
Example Question #1 : How To Find The Length Of An Edge Of A Prism
The volume of a prism is .
Given the length is and the height is , find the width of the prism.
The volume of a prism is length times width times height.
We are given the length is 7m and the width is 5m.
So, we plug these into our formula:
.
We then solve for height:
.
The height is therefore 6m.
Example Question #1 : How To Find The Length Of An Edge Of A Prism
Find the missing edge of the prism when its volume is .
The goal is to find the height of the rectangular prism with the given information of its width and length. The volume of a rectangular prism is , where is width and is height.
Because we're given the final volume and two of the three variables, we can substitute in the information we know and solve for the missing variable.
Therefore, the height of the prism is .
Example Question #1 : How To Find The Length Of An Edge Of A Prism
A rectangular prism has a volume of cubic meters. Its length is twice its width, and its height is twice its length. What is the length of the prism?
If we let be the width of our prism, then since the length is twice the width, our length would be . Since the height is twice the length, our height would be .
Since the volume of a rectangular prism is simply the product of width, length, and height, we get
We then simply solve for the width.
Therefore, our width is 3. Since our length is twice the width, the length is 6.
Example Question #2 : How To Find The Length Of An Edge Of A Prism
A right, rectangular prism has a volume of cubic inches. Its width is inches and its height is inches. What is its length?
None of the other answers.
The formula for the volume of a right, rectangular prism is , so substitute the known values and solve for lenght.
. So the length is 8 inches.
Example Question #1 : How To Find The Length Of An Edge Of A Prism
The surface area of a right rectangular prism is square cm. Its length is cm and its height is cm. Find the width of the prism.
None of the other answers.
Use the formula for finding the surface area of a right, rectangular prism,
and substitute the known values, and then solve for w.
So,
So, the width is 7 cm.
Example Question #2 : How To Find The Length Of An Edge Of A Prism
The height of a retangular prism is three times its width; its length is twice its width. Its surface area is 1,078 square inches. Give the width of the box.
Since the length of the box is twice the width and the height is three times the width, and .
The surface area of the box is
To find the width:
Example Question #1 : Prisms
Find the surface area of the rectangular prism:
To find the surface area of a prism, the problem can be approached in one of two ways.
1. Through an equation that uses lateral area
2. Through finding the area of each side and taking the sum of all the faces
Using the second method, it's helpful to realize rectangular prisms contain faces. With that, it's helpful to understand that there are pairs of sides. That is, there are two faces with the same dimensions. Therefore, we really only have three sides for which we need to calculate areas:
Faces 1 & 2:
Faces 3 & 4:
Faces 5 & 6:
Now, we can add up the areas of all six sides:
The surface area is .