Answer:
120 liters of the 10% solution should be mixed with 60 liters of a 25% solution to get a 15% solution.
Step-by-step explanation:
Let 'x' be the quantity of 10% solution
Given that we need determine many liters of a 10% solution should be mixed with 60 liters of a 25% solution to get a 15% solution.
As
10% of x = 0.1x
60 liters of a 25% = 60 × 0.25
Thus,
The equation becomes

Multiply both sides by 100


Subtract 1500 from both sides

Simplify

Subtract 15x from both sides

Simplify

Divide both sides by -5

Simplify

Therefore,
- 120 liters of the 10% solution should be mixed with 60 liters of a 25% solution to get a 15% solution.