Serena is making an experiment. For that, she needs 20 grams of a 52% solution of salt. She has two large bottles of salt water: one with 40% and the other with 70% of salt in them. How much of each must she use to make the solution she needs?

Question

Mathematics

Beef

16 October, 05:43

Serena is making an experiment. For that, she needs 20 grams of a 52% solution of salt. She has two large bottles of salt water: one with 40% and the other with 70% of salt in them. How much of each must she use to make the solution she needs?

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Answers (1)

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Angie Rosario · Answer 1

X + y = 20 - - > eqn 1

The second equation would be the mass balance shown below:

(x) (0.40) + y (0.70) = 20 (0.52) - - > eqn 2

Rearranging eqn 1, x = 20 - ySubstitute this to eqn 2:

(20 - y) (0.40) + y (0.70) = 20 (0.52) Solve for y, y = 8 grams Finally, solve for x. x = 20 - 8 = 12 grams

Therefore, Serena needs 12 grams of the 40% solution and 8 grams of the 70% solution.