Question 1026870
We have to make 50 ounces of a 60% acid solution. I have a 30% acid solution and an 80% acid solution to work with. How many ounces of the 30% acid solution and the 80% acid solution do I need? 
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Equations:
t + e = 50 ounces
30t + 80e = 60*50
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Modify for elimination:
30t + 30e = 30*50
30t + 80e = 60*50
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Subtract and sove for "e"::
50e = 30*50
e = 30 ounces (amt. of 80% needed)
t = 50-30 = 20 ounces (amt. of 30% needed)
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Cheers,
Stan H.
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