Percentage and Ratio

[Guest]

Sam wants to convert a mixture of acid and water in the ratio 16 : 19 to 19 : 16. What is the amount of acid as a percentage of initial solution that should be added to achieve the required ratio?

[HallsofIvy]

Sam wants to convert a mixture of acid and water in the ratio 16 : 19 to 19 : 16. What is the amount of acid as a percentage of initial solution that should be added to achieve the required ratio?

So you have to start with 16 units of acid and 19 units of water. Adding "x" units of acid you will have x+ 16 units of acid and 19 units of water. You want that to be "19: 16". So you want (x+ 16)/19= 19/16.

Can you solve that equation for x?

[mycalsuite]

Add acid equal to 18.75% of the initial solution to change the ratio from 16:19 to 19:16.