Answer :
The volume of the 12% salt solution to be added is; 2.5 gallons.
Ratio and Proportion of Volume
Let the volume of 12% required be x and the new volume of the mixture be (x+5).
On this note, it follows that;
- 12x + 15(5) = 14(5+x)
- 12x + 75 = 70 + 14x.
Hence, -2x = -5
Divide both side by -2;
- x = -5/-2
x = 2.5 gallons.
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