document.write( "Question 698706: find the surface area of a cylinder whose bases are circle with a radius of 18 inches and the height of the cylinder is 48 inches \n" ); document.write( "

Algebra.Com's Answer #431000 by Positive_EV(69) $\"\"$ $\"About$

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The surface area of a cylinder is equal to the sum of the areas of the circles on the top and bottom of the cylinder and the area around the cylinder.
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\n" ); document.write( "\n" ); document.write( "The area of a circle is $\"pi%2Ar%5E2\"$ , where r = 18, so $\"pi%2A18%5E2+=+324%2Api\"$ is the area of each circle.
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\n" ); document.write( "\n" ); document.write( "The area of the section between the circles is a bit trickier. You can think of this section as a rectangle rolled up into a cylindrical shape. This rectangle has a height of 48, and a width equal to the circumference of the circle, which is
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\n" ); document.write( "\n" ); document.write( " $\"2%2Api%2Ar+=+2%2Api%2A18+=+36%2Api\"$ .
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\n" ); document.write( "\n" ); document.write( "The area of this rectangle is equal to the height times the width, which is $\"48%2A%2836%2Api%29+=+1728%2Api\"$ .
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\n" ); document.write( "\n" ); document.write( "The sum of the area of the three parts is $\"324%2Api+%2B+324%2Api+%2B+1728%2Api+=+2376%2Api\"$ .
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\n" ); document.write( "\n" ); document.write( "The surface area is 2376*pi = 7464.424 square inches. \n" ); document.write( "

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