Mayra did not have a date on a friday night so she decided to mix solutions that she obtained from her garage. she has 9 liters of a 4% -saline solution that must be mixed with a 10% solution to get a 6% solution. how many liters of the 10% solution are needed?

Let be the number of liters of the 10% solution she needs to use. She'd end up with a 6% solution with a volume of liters. The starting solution contains 0.04*9 = 0.36 liter of salt. Each liter of the 10% solution contributes 0.1 liter of salt, so that

Solve for :

so Mayra needs to add 4.5 liters of the 10% solution.

Step-by-step explanation:

Swap sides so that all variable terms are on the left-hand side.

Multiply both sides by 5.

Dividing by undoes the multiplication by .

Divide by by multiplying by the reciprocal of

Hope it helps and have a great night! =D

~shining stars~