SOLUTION: A scientist has two solutions, which she has labeled Solution A and Solution B. Each contains salt. Combining 18 ounces of Solution A with 72ounces of Solution B gives 90 ounces of

Algebra ->  Percentage-and-ratio-word-problems -> SOLUTION: A scientist has two solutions, which she has labeled Solution A and Solution B. Each contains salt. Combining 18 ounces of Solution A with 72ounces of Solution B gives 90 ounces of      Log On


   

Question 609660: A scientist has two solutions, which she has labeled Solution A and Solution B. Each contains salt. Combining 18 ounces of Solution A with 72ounces of Solution B gives 90 ounces of a mixture that is 80% salt. Combining 40 ounces of Solution A with 10 ounces of Solution B gives 50 ounces of a mixture that is 65% salt.
What are the percentages of salt in the two solutions?

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
A scientist has two solutions, which she has labeled Solution A and Solution B. Each contains salt. Combining 18 ounces of Solution A with 72 ounces of Solution B gives 90 ounces of a mixture that is 80% salt.
Combining 40 ounces of Solution A with 10 ounces of Solution B gives 50 ounces of a mixture that is 65% salt.
What are the percentages of salt in the two solutions?
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Both Equations say salt + salt = salt
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18a + 72b = 80*90
40a + 10b = 65*50
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I used a matrix method to solve for a and b:
a = 60
b = 85
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The percentage of salt in solution A is 60%
The percentage of salt in solution B is 85%
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Cheers,
Stan H.