Question

Joy needs to mix a 30% alcohol solution with a 60% alcohol solution to create 100 mL of a 42% solution. How many ml of each solution must Joy use? How many millileters of 30% solution and how many millileters of 60% solution?

Answer 1

hav 30% & 60% stuf... want 100cc av 42%=42cc's av the stuf... 1: 0.3x +0.6y=42 2: x+y=100, so y=100-x... 0.3x +0.6*(100-x)=42... 0.3x -0.6x +60=42... -0.3x=42-60=-18... x=18/0.3=60, so y=40