document.write( "Question 732980: carl manages a highway department garage in maine. a mixture of salt and sand is stored in the garage for use during the winter. carl needs 24 tons of a salt/sand mixture that is 25% salt. he will combine shipments of 15% salt and shipments of 30% salt to achieve the desired 24 tons. how much of each type should he use? \n" ); document.write( "
Algebra.Com's Answer #448175 by josmiceli(19441)\"\" \"About 
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Let \"+a+\" = tons of 15% salt needed
\n" ); document.write( "Let \"+b+\" = tons of 30% salt needed
\n" ); document.write( "given:
\n" ); document.write( "(1) \"+a+%2B+b+=+24+\"
\n" ); document.write( "(2) \"+%28+.15a+%2B+.3b+%29+%2F+24+=+.25+\"
\n" ); document.write( "----------------------------
\n" ); document.write( "(2) \"+.15a+%2B+.3b+=+.25%2A24+\"
\n" ); document.write( "(2) \"+.15a+%2B+.3b+=+6+\"
\n" ); document.write( "(2) \"+15a+%2B+30b+=+600+\"
\n" ); document.write( "Multiply both sides of (1) by \"+15+\"
\n" ); document.write( "and subtract (1) from (2)
\n" ); document.write( "---------------------
\n" ); document.write( "(2) \"+15a+%2B+30b+=+600+\"
\n" ); document.write( "(1) \"+-15a+-+15b+=+-360+\"
\n" ); document.write( "\"+15b+=+240+\"
\n" ); document.write( "\"+b+=+16+\"
\n" ); document.write( "and, since
\n" ); document.write( "(1) \"+a+%2B+b+=+24+\"
\n" ); document.write( "(1) \"+a+=+8+\"
\n" ); document.write( "8 tons of 15% salt are needed
\n" ); document.write( "16 tons of 30% salt are needed
\n" ); document.write( "check:
\n" ); document.write( "(2) \"+%28+.15a+%2B+.3b+%29+%2F+24+=+.25+\"
\n" ); document.write( "(2) \"+%28+.15%2A8+%2B+.3%2A16+%29+%2F+24+=+.25+\"
\n" ); document.write( "(2) \"+%28+1.2+%2B+4.8+%29+%2F+24+=+.25+\"
\n" ); document.write( "(2) \"+6%2F24+=+.25+\"
\n" ); document.write( "(2) \"+6+=+.25%2A24+\"
\n" ); document.write( "(2) \"+6+=+6+\"
\n" ); document.write( "OK\r
\n" ); document.write( "\n" ); document.write( "
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