document.write( "Question 1102918: How many gallons of a 15% acid solution must be mixed with 5 gal of a 30% acid solution to make a 20% acid solution? \n" ); document.write( "

Algebra.Com's Answer #717651 by greenestamps(13203) $\"\"$ $\"About$

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\n" ); document.write( "The other tutor showed how to set up the problem using the standard algebraic method for solving \"mixture\" problems.

\n" ); document.write( "Here is a quick solution using a different method....

\n" ); document.write( "(1) The desired percentage, 20%, is \"twice as close\" to 15% as it is to 30%.
\n" ); document.write( "(2) That means the mixture must use twice as much of the 15% ingredient as the 30% ingredient.
\n" ); document.write( "(3) Since the problem says there are 5 gallons of the 30% ingredient, you need 10 gallons of the 15% ingredient. \n" ); document.write( "

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