Answer:
4 gallons of water should be added in 10% saline solution.
Step-by-step explanation:
Let x gallon of water is added in one gallon of 10% saline solution.
Therefore total volume of 10% saline solution will become (1 + x) gallons
Since concentration of water is 0% so equation will be
0.10(1) + 0(x) = .02(1 + x)
0.10 = 0.02(1 + x)
1 + x = [tex]\frac{0.10}{0.02}[/tex]
x + 1 = 5
x = 5 - 1
x = 4 gallons
Therefore, 4 gallons of water should be added to 10% saline solution to create 2% solution.