Question 1016521
A chemistry teacher needs to mix a 30% salt solution with a 90% salt solution to make 25 qt of a 54% solution. How many quarts of each solution should the teacher mix to get the desired result? 
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Quantity:: t + n = 25 qt
Salt::::: 30t+90n = 54*25
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Modify::
30t + 30n = 30*25
30t + 90n = 54*25
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Subtract and solve for "n"::
60n = 24*25
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n = 10 qts:: (amt. of 90%
t = 25-n = 15 qrs:: (amt. of 30% solution needed)
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Cheers,
Stan H.