document.write( "Question 119838: Hi, can you help me with this problem?\r
\n" ); document.write( "\n" ); document.write( "A storage bin for corn consists of a cylindrical section made of wire mesh, surmounted by a conical tin roof, as shown in the figure. The height of the roof is one-third the height of the entire structure. If the total volume of the structure is 2900 ft3 and its radius is 9 ft, what is its height? (Round the answer to one decimal place.)\r
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Algebra.Com's Answer #87842 by ankor@dixie-net.com(22740)\"\" \"About 
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A storage bin for corn consists of a cylindrical section made of wire mesh, surmounted by a conical tin roof, as shown in the figure. The height of the roof is one-third the height of the entire structure. If the total volume of the structure is 2900 ft3 and its radius is 9 ft, what is its height? (Round the answer to one decimal place.)
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\n" ); document.write( "Let h = height of the cylindrical section only
\n" ); document.write( "Then
\n" ); document.write( ".5h = height of the conical section only (.5h is 1/3 of 1.5h, the total height)
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\n" ); document.write( "We know:
\n" ); document.write( "vol of a cylinder = pi*r^2*h
\n" ); document.write( "vol of a cone = (1/3)*pi*r^2*h
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\n" ); document.write( "Given:
\n" ); document.write( "Vol of the cylinder + vol of the cone = 2900 cu/ft
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\n" ); document.write( "pi*9^2*h + (1/3*pi*9^2*.5h = 2900
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\n" ); document.write( "pi*81*h + (1/3)*pi*81*.5h = 2900
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\n" ); document.write( "pi*81*h + pi*27*.5h = 2900; took (1/3) of 81
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\n" ); document.write( "254.469h + 42.4115h = 2900
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\n" ); document.write( "296.88h = 2900
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\n" ); document.write( "h = 2900/296.88
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\n" ); document.write( "h = 9.768 ft is the height of the cylinder
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\n" ); document.write( "4.88 ft is the height of the cone
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\n" ); document.write( "9.768 + 4.88 = 14.6 ft is the total height
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\n" ); document.write( "Check solution using 9.8 for ht of the cylinder and 4.9 for the ht of the cone
\n" ); document.write( "pi*9^2*9.8 = 2493.8 cu ft (cylinder)
\n" ); document.write( "(1/3)*pi*9^2*4.9 = 415.6 cu ft (cone)
\n" ); document.write( "2493.8 + 415.6 = 2909.4 ~ 2900 (we rounded both values upward)
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\n" ); document.write( "Did this help?
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