document.write( "Question 118111: chemist mixes an 8% hydrochloric acid solution with a 5% hydrochloric acid solution. How many milliliters of the 5% solution should the chemist use to make a 750-milliliter solution that is 7% hydrochloric acid? \n" ); document.write( "

Algebra.Com's Answer #86210 by Earlsdon(6294) $\"\"$ $\"About$

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Let x = the number of milliliters of the 5% hydrochloric acid solution.
\n" ); document.write( "Then,(750-x) = the number of milliliters of the 8% hydrochloric acid solution.
\n" ); document.write( "The sum of these two amounts is to equal 750 milliliters of 7% hydrochloric acid solution.
\n" ); document.write( "The amount of hydrochloric acid in each of these amounts of solution can be written:
\n" ); document.write( " $\"x%280.05%29%2B%28750-x%29%280.08%29+=+750%280.07%29\"$ Simplify and solve for x.
\n" ); document.write( " $\"%280.05x%29%2B%2860-0.08x%29+=+52.5\"$ Combine like-terms.
\n" ); document.write( " $\"-0.03x%2B60+=+52.5\"$ Subtract 60 from both sides.
\n" ); document.write( " $\"-0.03x+=+-7.5\"$ Divide both sides by -0.03
\n" ); document.write( " $\"x+=+250\"$
\n" ); document.write( "The chemist will require 250 ml of the 5% hydrochloric acid solution. \n" ); document.write( "

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