Question 996176
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 
180
 ounces of a mixture that is 
55%
 salt. How many ounces of each solution should she use?
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f = amount of 45%
s = amount of 70%
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f + s = 180 (total solution)
45f + 70s = 55*180 (total salt)
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Solve for f & s