document.write( "Question 1156383: Misty wishes to obtain 85 ounces of a 40% acid solution by combining a 72% acid solution with a 25% acid solution. How much of each solution should misty use? \n" ); document.write( "
Algebra.Com's Answer #779079 by greenestamps(13203) You can put this solution on YOUR website! \n" ); document.write( "You should understand how to solve a two-part mixture problem like this using formal algebra. But if a formal algebraic solution is not required, there is a MUCH faster way to solve the problem. \n" ); document.write( "A typical algebraic solution would look something like this.... \n" ); document.write( "x = ounces of 72% acid \n" ); document.write( "85-x = ounces of 25% acid \n" ); document.write( "The combined acid in the two ingredients is equal to the acid in 40% of the total 85 ounces: \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "The amount of 72% acid is 1275/47 ounces; the amount of 25% acid is 85-(1275/47) = 2720/47 ounces. Those are ugly fractions; and we had to do a lot of ugly calculations to find them. \n" ); document.write( "Convert those numbers to decimals or percents if required.... \n" ); document.write( "Here is a much faster path to the same ugly answers. \n" ); document.write( "On a number line, 40% is 15/47 of the way from 25% to 72%. \n" ); document.write( "That means 15/47 of the mixture needs to be the 72% acid. \n" ); document.write( "15/47 of the total 85 ounces is 1275/47 ounces. \n" ); document.write( " \n" ); document.write( " |