document.write( "Question 663147: I need 25 lb of a combination of product A 27 lb/cube ft & product B 13 lb/cube ft how much of each will I need. What is the formula?\r
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Algebra.Com's Answer #412646 by ankor@dixie-net.com(22740)\"\" \"About 
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I need 25 lb of a combination of product A 27 lb/cube ft & product B 13 lb/cube ft how much of each will I need.
\n" ); document.write( " What is the formula?
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\n" ); document.write( "You must specify the amt per cu/ft you want the resulting 25 lbs to be
\n" ); document.write( "It has to be between 27 and 13, as an example I am going to say 18 lb/cuft
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\n" ); document.write( "Let a = amt of product A
\n" ); document.write( "then
\n" ); document.write( "(25-a) = amt of product B
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\n" ); document.write( "27a + 13(25-a) = 18(25)
\n" ); document.write( "27a + 325 - 13a = 450
\n" ); document.write( "27a - 13a = 450 - 325
\n" ); document.write( "14a = 125
\n" ); document.write( "a = 125/14
\n" ); document.write( "a = 8.93 lb of product a
\n" ); document.write( "then
\n" ); document.write( "(25-8.93) = 16.07 lb of product b
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\n" ); document.write( "If you wish to have a resulting 25 lb which 20 lb/cuft, half way between 13 & 27
\n" ); document.write( "just have 12.5 lb of each product\r
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