Question 1025706
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A scientist has two solutions, which she has labeled Solution A and Solution B. Each contains salt. 
She knows that Solution A is 45% salt and Solution B is 70% salt. She wants to obtain 70 ounces of a mixture 
that is 55% salt. How many ounces of each solution should she use?
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        Calculations in the post by @lwsshak3 are incorrect, giving wrong answer.

        I came to bring a correct solution.



solution A = x ounces
Solution B = (70-x) ounces
let x = Amt of solution A used
70-x = Amt of solution B used
0.45x + 0.7*(70-x) = 0.55*70
0.45x + 49 - 0.7x = 38.5
0.25x = 10.5
x = 10.5/0.25 = 42.
70-x = 28
Amt of solution A used = 42 ounces
Amt of solution B used = 28 ounces


<U>CHECK</U> &nbsp;&nbsp;for the final concentration  &nbsp;&nbsp;&nbsp;&nbsp;{{{(0.45*42 + 0.7*28)/70}}} = 0.55, or 55%.  &nbsp;&nbsp;&nbsp;&nbsp;! precisely correct !


Solved correctly.