There are 74.227 milliliters of acid in the solution.
Step-by-step explanation:
- The total amount of liquid is 373 milliliters. This is both the acid and water combined i.e amount of liquid + amount of acid = 373 milliliters
- If 19.9% of this is acid it means 19.9% of the the entire 373 milliliters is acid. So we calculate how much 19.9% of 373 milliliters is.
- 19.9% of 373 milliliters = 0.199 × 373 = 74.227 milliliters. So 74.227 milliliters of the entire solution is acid.