Question

In the lab, Soo has two solutions that contain alcohol and is mixing them with each other. Solution A is 2% alcohol and solution B is 6% alcohol. She uses 600 milliliters of solution A. How many milliliters of solution B does she use, if the resulting mixture is a 5% alcohol solution?

Answer 1

Compute the amount of alcohol in each quantity.

600 mL of solution A = 600 mL * 2% = 600 mL*2/100 = 12 mL of alcohol

When she adds the 600 mL of solution A to the x mL of other solution (which contains 6%*x mL of alcohol), she's going to end up with 600+x mL of solution at 5%, which will contain 0.05*(600+x) mL of alcohol. Write that out and solve for \(x\).