Question 1154014
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...and I prefer to solve this kind of problem using 0 variables....<br>
Here is the quick and easy solution to this problem:<br>
(1) The target 25% is 1/5 of the way from 20% to 45%.  (20 to 45 is a difference of 25; 20 to 25 is a difference of 5; 5/25 = 1/5)
(2) That means 1/5 of the mixture has to be the 45% ingredient.<br>
ANSWER: 1/5 of 10 gallons, or 2 gallons, of the 45% alcohol solution; 10-2=8 gallons of the 20% alcohol solution.<br>