document.write( "Question 95073: A steel storage tank for propane gas is to be constructed in the shape of a right cylinder with a hemisphere at each end. the construction cost per square foot of the end pieces is $4.00, while the cylindrical part costs $2.00 per square foot. If the tank needs to hold 10(pi symbol)ft^3 of propane gas, what dimensions minimize the cost of construction? What is the minimum cost? \n" ); document.write( "
Algebra.Com's Answer #69165 by stanbon(75887)\"\" \"About 
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A steel storage tank for propane gas is to be constructed in the shape of a right cylinder with a hemisphere at each end. the construction cost per square foot of the end pieces is $4.00, while the cylindrical part costs $2.00 per square foot. If the tank needs to hold 10(pi symbol)ft^3 of propane gas, what dimensions minimize the cost of construction? What is the minimum cost?
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\n" ); document.write( "Let the radius be \"x\" feet.
\n" ); document.write( "Area of the combined semi-circular end pieces = 4pir^2 = 4(pi)x^2
\n" ); document.write( "Volume of the combined semi-circular end pieces = (4/3)(pi)x^3
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\n" ); document.write( "Area of the cylindrical part = 2(pi)xh
\n" ); document.write( "Volume of the cylindrical part = (pi)x^2h
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\n" ); document.write( "EQUATION:
\n" ); document.write( "volumn + volumn = volumn
\n" ); document.write( "(4/3)(pi)x^3 + (pi)x^2h = 10(pi)
\n" ); document.write( "(4/3)x^3 + x^2h - 10 = 0
\n" ); document.write( "Comment: Not knowing \"h\" results in not knowing \"x\".
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\n" ); document.write( "Price equation:
\n" ); document.write( "price + price = total price
\n" ); document.write( "4[4(pi)x^2] + 2[2(pi)xh] = total price
\n" ); document.write( "Comment: Not knowing \"h\" results in not being able to find the minimum here.
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.\r
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