All Common Core: 8th Grade Math Resources
Example Questions
Example Question #171 : Geometry
The height of a cylinder is two times the length of the radius of the circular end of a cylinder. If the volume of the cylinder is , what is the height of the cylinder?
The volume of a cylinder is:
where is the radius of the circular end of the cylinder and is the height of the cylinder.
Since , we can substitute that into the volume formula. So we can write:
So we get:
Example Question #172 : Geometry
The end (base) of a cylinder has an area of square inches. If the height of the cylinder is half of the radius of the base of the cylinder, give the volume of the cylinder.
The area of the end (base) of a cylinder is , so we can write:
The height of the cylinder is half of the radius of the base of the cylinder, that means:
The volume of a cylinder is found by multiplying the area of one end of the cylinder (base) by its height:
or
Example Question #173 : Geometry
We have two right cylinders. The radius of the base Cylinder 1 is times more than that of Cylinder 2, and the height of Cylinder 2 is 4 times more than the height of Cylinder 1. The volume of Cylinder 1 is what fraction of the volume of Cylinder 2?
The volume of a cylinder is:
where is the volume of the cylinder, is the radius of the circular end of the cylinder, and is the height of the cylinder.
So we can write:
and
Now we can summarize the given information:
Now substitute them in the formula:
Example Question #174 : Geometry
Two right cylinders have the same height. The radius of the base of the first cylinder is two times more than that of the second cylinder. Compare the volume of the two cylinders.
The volume of a cylinder is:
where is the radius of the circular end of the cylinder and is the height of the cylinder. So we can write:
We know that
and
.
So we can write:
Example Question #113 : Volume Of A Three Dimensional Figure
A cylinder has a diameter of inches and a height of inches. Find the volume, in cubic inches, of this cylinder.
Since we are given the diameter, divide that value in half to find the radius.
Now plug this value into the equation for the volume of a cylinder.
Example Question #1993 : Hspt Mathematics
Find the volume, in cubic inches, of a cylinder that has a radius of inches and a height of inches.
The formula to find the volume of a cylinder is .
Now, plug in the given numbers into this equation.
Example Question #731 : Geometry
Find the volume of the cylinder if the circular base has an area of , and the height of the cylinder is also .
Write the formula for volume of a cylinder.
Remember that area of a circle is
Since the area of the circle is known, substitute the area into the formula.
Example Question #175 : Geometry
A car dealership wants to fill a large spherical advertising ballon with helium. It can afford to buy 1,000 cubic yards of helium to fill this balloon. What is the greatest possible diameter of that balloon (nearest tenth of a yard)?
The volume of a sphere, given its radius, is
Set , solve for , and double that to get the diameter.
The diameter is twice this, or 12.4 yards.
Example Question #176 : Geometry
The diameter of a sphere is . Give the volume of the sphere in terms of .
The diameter of a sphere is so the radius of the sphere would be
The volume enclosed by a sphere is given by the formula:
Example Question #177 : Geometry
A spherical balloon has a diameter of 10 meters. Give the volume of the balloon.
The volume enclosed by a sphere is given by the formula:
where is the radius of the sphere. The diameter of the balloon is 10 meters so the radius of the sphere would be meters. Now we can get: