SOLUTION: How many cups of a 18% salt solution must be added to 16 cups of a 25% salt solution to get a 20% salt solution? a. 20 cups b. 30 cups c. 40 cups or d. 55.5 cups

Algebra ->  Percentage-and-ratio-word-problems -> SOLUTION: How many cups of a 18% salt solution must be added to 16 cups of a 25% salt solution to get a 20% salt solution? a. 20 cups b. 30 cups c. 40 cups or d. 55.5 cups      Log On


   

Question 576574: How many cups of a 18% salt solution must be added to 16 cups of a 25% salt solution to get a 20% salt solution?
a. 20 cups
b. 30 cups
c. 40 cups
or
d. 55.5 cups
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
How many cups of a 18% salt solution must be added to 16 cups of a 25% salt solution to get a 20% salt solution?
a. 20 cups
b. 30 cups
c. 40 cups
or
d. 55.5 cups
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Equation:
salt + salt = salt
0.18x + 0.25*16 = 0.20(x+16)
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Multiply thru by 100 to get:
18x + 25*16 = 20x + 20*16
2x = 5*16
x = 40 cups (# of cups of 18% solution)
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Cheers,
Stan H.
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