Question 1046904
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An experiment calls for a 5% salt solution. Only a 3% salt solution and an 6% salt solution are available. 
How many gallons of each must be combined to obtain 30 gallons of a 5% salt solution?
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0.03x+0.06(30-x) = 0.05(30)
0.03x+1.8-0.06x = 1.5
-0.03x = -0.3 Divide.
x = 10
You'll need 10 gallon of the 3% solution and 30-10 = 20 gallon of the 6% solution to obtain 30 gallon of a 5% solution