A pharmacist has 600 milliliters of a solution that is 30% active ingredient. How much pure water should she add to the solution to get a solution that is 15% active ingredient?

600 ml of pure water.

Step-by-step explanation:

To determine how much pure water the pharmacist should add to a 600ml solution with 30% active ingredient, so that this solution becomes 15%, the following calculation must be performed:

600 x 0.3 = 180

15 = 180

100 = X

100 x 180/15 = X

18,000 / 15 = X

1,200 = X

1,200 - 600 = 600

Thus, 600 ml of pure water should be added to achieve a 15% solution.

175

step-by-step explanation:

2 inches x 10 miles = 200 miles - 3 inches = 175

7 ft 6 in means 7 1/2, because 6 in is 1/2 of a foot. 7 ft 8 in means 7 2/3 because 8 in is 2/3 of a foot. 23/3 = 7 2/3. 15/2 = 7 1/2.

23/3   *   15/2   = 57 1/2

step-by-step explanation: