Problema Solution
A chemist needs 12 L of a 40% alcohol solution. She must mix a 20% solution and a 50% solution. How many liters of each will be required to obtain what she needs?
Answer provided by our tutors
x + y = 12
2x + 5y = 4*12
=> 24-2y+5y=48
3y=24
y=8 , x=4