document.write( "Question 198073: How much soil containing 45% sand do you need
\n" ); document.write( "to add to 1 ftł of soil containing 15% sand in order
\n" ); document.write( "to make a soil containing 35% sand? \n" ); document.write( "

Algebra.Com's Answer #148551 by josmiceli(19441) $\"\"$ $\"About$

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Let $\"x\"$ = ft3 of 45% sand soil needed
\n" ); document.write( "In words:
\n" ); document.write( "{ft3 sand in final mixture)/(total ft3 of mixture) = 35%
\n" ); document.write( " $\"%28.45x+%2B+.15%2A1%29+%2F+%28x+%2B+1%29+=+.35\"$
\n" ); document.write( "Multiply both sides by $\"x+%2B+1\"$
\n" ); document.write( " $\".45x+%2B+.15+=+.35%2A%28x+%2B+1%29\"$
\n" ); document.write( " $\".45x+%2B+.15+=+.35x+%2B+.35\"$
\n" ); document.write( " $\".1x+=+.2\"$
\n" ); document.write( " $\"x+=+2\"$
\n" ); document.write( "2 ft3 of 45% sand soil is needed
\n" ); document.write( "check:
\n" ); document.write( " $\"%28.45%2A2+%2B+.15%2A1%29+%2F+%282+%2B+1%29+=+.35\"$
\n" ); document.write( " $\"%28.9+%2B+.15%29+%2F+3+=+.35\"$
\n" ); document.write( " $\"1.05%2F3+=+.35\"$
\n" ); document.write( " $\".35+=+.35\"$
\n" ); document.write( "OK \n" ); document.write( "

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