<PRE><B>Question 251728</B>
9 gal. of a sugar solution was mixed with 6 gallon of a 90% sugar solution to make a 84% sugar solution. Find the percent concentration of the first solution. 
Ans: 
Let x= percentage of sugar concentration in 9 gallons
(9*x)+(6*.9)=15*.84 
Simplfy: 
9x+5.4=12.6 
Solve: 
9x=12.6-5.4
9x=7.2
x=7.2/9
x=.8 
Converted in to percent, .8 is equal to 80%, so our answer is that there is 80% of sugar concentration in a 9 gallon sugar solution.

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