Mixture Problem

Question

A chemist wants to create a 40% acid solution from the two solutions she has on hand. She has a 70% an a 10% solution. How much of each must she mix together to get 125 ml of 40% acid solution. She suspects she will need to add equal amounts of each to get the final concentration. Solve this Mathematically.

Answer 1

X+y = 125

0.7x + 0.1y = 0.4*125 = 50

7x + y = 500

7x + 125-x = 500

6x + 125 = 500

6x = 3 75

x = 62.5

y = 62.5

62.5 mL of each