Question 1059105
Let the amount of solution at 20% be x. Then, the amount at 5% will be 300-x.
:
0.20x+0.05(300-x) = 0.19(300)
0.20x+15-0.05x = 57
0.15x = 42 divide both sides by 0.15 to get the amount at 20%. Then subtract that amount from 300 to get your amount at 5% (this amount will be very small. Why? Because you want the result to be a 19% solution, so the amount you want is much, much closer to 20% than to 5%, meaninng you'll need a lot more of the solution at 20%)
Email if you have questions.
John