Question 528204
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Let *[tex \Large x] represent the number of liters of 30% solution to be added.  Then *[tex \Large 0.3x] is the amount of acid in the 30% solution.  Likewise, *[tex \Large 0.7(10)] is the amount of acid in the 10 liters of 70% solution, and *[tex \Large 0.6(x\ +\ 10)] is the amount in the mixture.  So:


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ 0.3x\ +\ 7\ =\ 0.6(x\ +\ 10)]


Solve for *[tex \Large x].


John
*[tex \LARGE e^{i\pi} + 1 = 0]
My calculator said it, I believe it, that settles it
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