What quantity of a 70% alcohol solution must be mixed with a 0% alcohol solution to produce 1000ml of an 18% solution

Question

solve quantities for a solution mix

Answer 1

 What quantity of a 70% alcohol solution must be mixed with a 0% alcohol solution to produce 1000ml of an 18% solution

1,000 ml of 18% solution will contain 180 ml alcohol.

Let V1 be the volume of 70% alcohol solution used.

Let V2 be the volume of 0% alcohol solution used.

V1 @ 70% = 0.7V1 ml of alcohol

V2 @ 0% = 0 ml of alcohol

Summing these alcoholvolumes, 0.7V1 + 0 = 0.7V1 ml

i.e. 0.7V1 = 180

V1 = 257.14ml of 70% alcohol

V2 = 1,000 -257.14 = 742.86 ml

The final solution of 1,000 ml of 18% alcohol solution is made up from

257.14 ml of 70% solution with 742.86 ml of 0% solution