<PRE><B>Question 198051</B>
9 gallons of a sugar solution was mixed with 6 gallons of a 90% sugar
 solution to make a 84% sugar solution. FInd the percent concentration
 of the first solution.
:
Let x = the percent of the 9 gallon sugar solution
:
9x + 90(6) = 84(9+6)
:
9x + 540 = 1260
:
9x = 1260 - 540
:
9x = 720
x = {{{720/9}}}
x = 80% is the 1st solution
;
:
Check:
80(9) + 90(6) = 84(15)
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