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Example Questions
Example Question #1391 : Concepts
A perfect cube has a volume of 8 cubic centimeters. If the height, length and width of the cube were doubled, what would be the volume of the cube?
Volume is calculated by height x width x length:
For a cube, the height, width, and length are all the same value, so the equation can be simplified to , where is the length of one edge of the cube.
We know that for the initial cube, , so we can substitute this into the volume equation and solve for the length of one of the cube's sides:
So, one edge of the initial cube is long. When doubled, the cube will have edges that are each long. We can solve for the final volume of the cube by substituting into the equation for the volume of a cube and solving:
Example Question #1 : Cones
An empty tank in the shape of a right solid circular cone has a radius of r feet and a height of h feet. The tank is filled with water at a rate of w cubic feet per second. Which of the following expressions, in terms of r, h, and w, represents the number of minutes until the tank is completely filled?
π(r2)(h)/(180w)
180w/(π(r2)(h))
π(r2)(h)/(60w)
π(r2)(h)/(20w)
20w/(π(r2)(h))
π(r2)(h)/(180w)
The volume of a cone is given by the formula V = (πr2)/3. In order to determine how many seconds it will take for the tank to fill, we must divide the volume by the rate of flow of the water.
time in seconds = (πr2)/(3w)
In order to convert from seconds to minutes, we must divide the number of seconds by sixty. Dividing by sixty is the same is multiplying by 1/60.
(πr2)/(3w) * (1/60) = π(r2)(h)/(180w)
Example Question #1 : How To Find The Volume Of A Cone
A cone has a base radius of 13 in and a height of 6 in. What is its volume?
None of the other answers
1352π in3
338π in3
1014π in3
4394π in3
338π in3
The basic form for the volume of a cone is:
V = (1/3)πr2h
For this simple problem, we merely need to plug in our values:
V = (1/3)π132 * 6 = 169 * 2π = 338π in3
Example Question #3 : Cones
A cone has a base circumference of 77π in and a height of 2 ft. What is its approximate volume?
8893.5π in3
142,296π in3
11,858π in3
71,148π in3
2964.5π in3
11,858π in3
There are two things to be careful with here. First, we must solve for the radius of the base. Secondly, note that the height is given in feet, not inches. Notice that all the answers are in cubic inches. Therefore, it will be easiest to convert all of our units to inches.
First, solve for the radius, recalling that C = 2πr, or, for our values 77π = 2πr. Solving for r, we get r = 77/2 or r = 38.5.
The height, in inches, is 24.
The basic form for the volume of a cone is: V = (1 / 3)πr2h
For our values this would be:
V = (1/3)π * 38.52 * 24 = 8 * 1482.25π = 11,858π in3
Example Question #1 : How To Find The Volume Of A Cone
What is the volume of a right cone with a diameter of 6 cm and a height of 5 cm?
The general formula is given by , where = radius and = height.
The diameter is 6 cm, so the radius is 3 cm.
Example Question #1 : Cones
There is a large cone with a radius of 4 meters and height of 18 meters. You can fill the cone with water at a rate of 3 cubic meters every 25 seconds. How long will it take you to fill the cone?
First we will calculate the volume of the cone
Next we will determine the time it will take to fill that volume
We will then convert that into minutes
Example Question #1 : How To Find The Volume Of A Cylinder
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 #1 : How To Find The Volume Of A Cylinder
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 #3 : How To Find The Volume Of A Sphere
A sphere has a diameter of inches. What is the volume of this sphere?
To find the volume of a sphere, use the following formula:
, where is the radius of the sphere.
Now, because we are given the diameter of the sphere, divide that value in half to find the radius.
Now, plug this value into the volume equation.
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