<PRE><B>Question 991568</B>
Do it like this one:
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A large solar heating panel requires 110 gallons of a fluid that is 40% antifreeze. The fluid comes in either a 65% solution or a 20% solution. How many gallons of each should be used to prepare the 110-gallon solution?
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s = amount of 65%
t = amount of 20%
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s + t = 111  (total solution)
65s + 20t = 40*110  (total antifreeze)
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