McGraw Hill Integrated II, 2012
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McGraw Hill Integrated II, 2012 View details
4. Volumes of Prisms and Cylinders
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Exercise 18 Page 835

Use the Pythagorean Theorem and the formula for the volume of a cylinder.

823 in^3

Practice makes perfect

The given solid is a cylinder.

Let's recall the formula for the volume of a cylinder, where r is its radius and h is its height. V=π r^2 h

Let's first find the height of the cylinder and then calculate its volume.

Finding the Height of the Cylinder

We can see from the diagram that the cylinder's diameter is 11in. With the given diagonal of length 14in. and the height h they form a right triangle.

We can use the Pythagorean Theorem to calculate the cylinder's height. a^2+b^2=c^2 We know that a = 11 in. and c = 14 in. Let's use this information to find the length of b.
a^2+b^2=c^2
( 11)^2+b^2=( 14)^2
Solve for b
121+b^2=196
b^2=75
b=sqrt(75)
b= 8.660254...
b ≈ 8.66
We have found that the height of the given cylinder, b, is approximately 8.66.

Calculating the Volume of the Cylinder

We are given the diameter of the cylinder. Let's recall the relation between the diameter and radius of a circle. d=2r We can substitute the diameter into the formula and calculate r.
d = 2r
11 = 2r
5.5 = r
r = 5.5
Next, let's substitute the radius and height of the cylinder into the appropriate formula and calculate the volume of the cylinder.
V=π r^2 h
V=π ( 5.5)^2 ( 8.66)
Simplify right-hand side
V=π( 30.25)( 8.66)
V=261.965π
V=822.987319...
V≈ 823
The approximate volume of the given cylinder is 823 in^3.