document.write( "Question 35172: Two alloys, alloy A and alloy B, are to be melted down to form another alloy. Alloy B is 19 percent iron. If 42 kg of alloy A and 84 kg of alloy B are melted down and mixed, you will get a new alloy of 31 percent iron. How much iron is contained the alloy A? Express your answer in percentage. Put % after your answer.
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Algebra.Com's Answer #21380 by stanbon(75887)\"\" \"About 
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Two alloys, alloy A and alloy B, are to be melted down to form another alloy. Alloy B is 19 percent iron. If 42 kg of alloy A and 84 kg of alloy B are melted down and mixed, you will get a new alloy of 31 percent iron. How much iron is contained the alloy A?\r
\n" ); document.write( "\n" ); document.write( "Let percentage of iron in alloy A be \"x\"
\n" ); document.write( "Amount of iron in alloy A is 42x
\n" ); document.write( "Amount of iron in alloy B s 0.19(84)=16.0 kg
\n" ); document.write( "EQUATION:
\n" ); document.write( " iron + iron = 0.31(126)=39.1 kg
\n" ); document.write( "42x + 16 = 39.1
\n" ); document.write( "42x=23.1
\n" ); document.write( "x=0.55= 55%
\n" ); document.write( "The percentage of iron in alloy A is 55%
\n" ); document.write( "Amount of iron in alloy A = 0.55(42 kg)= 23.1 kg
\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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