document.write( "Question 749867: An engineer wants to make a 60% cement mixture. How many pounds of an 80% cement mixture must she mix with 14 pounds of a 50% mixture to create a 60% cement mixture? \n" ); document.write( "

Algebra.Com's Answer #456191 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Pounds of cement in 50% mix = $\"+.5%2A14+=+7+\"$
\n" ); document.write( "Let $\"+x+\"$ = pounds of 80% mix needed
\n" ); document.write( " $\"+.8x+\"$ = pounds of cement in 80% mix
\n" ); document.write( "-----------------------------------
\n" ); document.write( " $\"+%28+7+%2B+.8x+%29+%2F+%28+14+%2B+x+%29+=+.6+\"$
\n" ); document.write( " $\"+7+%2B+.8x+=+.6%2A%28+14+%2B+x+%29+\"$
\n" ); document.write( " $\"+7+%2B+.8x+=+8.4++%2B+.6x+\"$
\n" ); document.write( " $\"+.2x+=+1.4+\"$
\n" ); document.write( " $\"+x+=+7+\"$
\n" ); document.write( "7 pounds of 80% mix are needed
\n" ); document.write( "check:
\n" ); document.write( " $\"+%28+7+%2B+.8x+%29+%2F+%28+14+%2B+x+%29+=+.6+\"$
\n" ); document.write( " $\"+%28+7+%2B+.8%2A7+%29+%2F+%28+14+%2B+7+%29+=+.6+\"$
\n" ); document.write( " $\"+12.6+%2F+21+=+.6+\"$
\n" ); document.write( " $\"+12.6+=+.6%2A21+\"$
\n" ); document.write( " $\"+12.6+=+12.6+\"$
\n" ); document.write( "OK \n" ); document.write( "

\n" );