Question

A lab technician mixes a 10% acid solution with a 50% acid solution to create 40 ml of a 40%

solution. How much of each solution must be used?

Answer 1

10 ml of 10%

30 ml of 50%

Explanation:

x = amount of 10%

40 - x = amount of 50%

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10x + 50(40 - x) = 40(40)

10x + 2000 - 50x = 1600

-40x + 2000 = 1600

-40x = -400

x = 10 ml of 10%

40 - x = 30 ml of 50%