document.write( "Question 624863: A merchents has coffee worth $60 a pound that she wants to mix with 70 pounds of coffe worth $90 a pound to get a mixture that is worth $70 a pound. How many pounds (lbs) of the $60 coffee should be used? \n" ); document.write( "
Algebra.Com's Answer #393175 by Maths68(1474)\"\" \"About 
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Coffee-A
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\n" ); document.write( "Worth = $60/pound
\n" ); document.write( "Weight=x pounds\r
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\n" ); document.write( "\n" ); document.write( "Coffee-B
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\n" ); document.write( "Worth = $90/pound
\n" ); document.write( "Weight= 70 pounds\r
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\n" ); document.write( "\n" ); document.write( "Mixture
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\n" ); document.write( "Worth = $70/pound
\n" ); document.write( "Weight= (x+70) pounds\r
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\n" ); document.write( "\n" ); document.write( "(Coffee-A worth)*(Coffee-A weight) + (Coffee-B worth)*(Coffee-B weight) = (Mixture worth)*(Mixture weight)
\n" ); document.write( "(60)(x)+(90)(70)=(70)(x+70)
\n" ); document.write( "60x+6300=70x+4900
\n" ); document.write( "60x-70x=4900-6300
\n" ); document.write( "-10x=-1400
\n" ); document.write( "Divide by -10 both sides of above equation
\n" ); document.write( "-10x/-10=-1400/10
\n" ); document.write( "x=140\r
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\n" ); document.write( "\n" ); document.write( "She should mix 140 pounds of coffee worth $60 a pound with 70 pounds of coffee worth $90 a pound to get a mixture that is worth $70 a pound
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