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You can put this solution on YOUR website!
\n" ); document.write( "A traditional method for solving this kind of problem using formal algebra....
\n" ); document.write( "The thing we are looking for is the amount of 4% salt solution to use, so we can use that as our variable.
\n" ); document.write( "let x = amount of 4% salt solution
\n" ); document.write( "then 600-x = amount of 16% salt solution (because the total amount is 600ml)
\n" ); document.write( "The x amount of 4% salt solution, combined with the (600-x) amount of 16% salt solution, yields 600ml of 10% salt solution:
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\n" ); document.write( "Solve using basic algebra; I leave that to you.
\n" ); document.write( "Here is a much easier and faster way to solve this kind of mixture problem involving two ingredients.
\n" ); document.write( "Think of starting with the 4% solution and adding some of the 16% solution, stopping when the mixture reaches 10%.
\n" ); document.write( "Now model that by starting at 4% on a number line and moving towards 16%, stopping at 10%.
\n" ); document.write( "The distance from 4% to 16% is 12; the distance from 4% to 10% is 6. In moving from 4% towards 16% and stopping at 10%, the fraction of the total distance you have moved is 6/12 = 1/2.
\n" ); document.write( "That fraction 1/2 is then the fraction of the mixture that needs to be the 16% salt solution that you are adding.
\n" ); document.write( "So half of the mixture should be the 16% salt solution and the other half should be the 4% salt solution.
\n" ); document.write( "So the 600ml mixture should be made using 300ml of each ingredient.
\n" ); document.write( "Note an experienced problem solver could answer this problem almost immediately. Since the 10% is halfway between the 4% and the 16%, it is common sense that the mixture should use equal parts of the two ingredients.
\n" ); document.write( "All the words of explanation make this look like a long a tedious method for solving the problem; but it is in fact very fast and simple. Without all the words, here is the complete solution:
\n" ); document.write( "16-4 = 12; 10-4 = 6; 6/12 = 1/2
\n" ); document.write( "1/2 of the 600ml is the 16%; the other half is the 4%
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