Question 1095079: Milk and cream contain different percents of butterfat. How much 3% milk needs to be mixed with how much 15% cream to give 20 L of 6%? Found 3 solutions by josgarithmetic, ikleyn, greenestamps:Answer by josgarithmetic(39620) (Show Source):
You can put this solution on YOUR website! one answer that is not an answer but rather a reference to a place where you can see her method of solving the problem; and another answer without any clue to you about how to get that answer....
You can follow the path the first responder gave you, to try a solution by the traditional algebraic method. But give this shortcut method a try and see if you understand it; if you do, you will be able to solve mixture problems like this with much less work.
You are mixing ingredients with butterfat percentages of 3% and 15% to get a mixture of 6% butterfat. Look at how far the 6% is from each of the 15% and 3%:
15-6 = 9
6-3 = 3
The 6% is "3 times as close" to 3% as it is to 15% (because 9 is 3 times as much as 3). That means you need 3 times as much of the 3% milk as you need of the 15% cream.
3 times as much milk as cream and a total of 20 L means 15 L of the 3% milk and 5 L of the 15% cream.
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