Question 1015686
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S=amount of 65%; E=amount of 85%
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0.65S+0.85E=0.77(S+E)
0.65S+0.85(9)=0.77(S+9)
0.65S+7.65=0.77S+6.93
0.72=0.12S
6=S
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ANSWER: 6 liters of 65% solution should be used.
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