SOLUTION: Please help me solve this mixture: You need a 25% alcohol solution. On hand, you have a 20 mL of a 15% alcohol mixture. You also have 30% alcohol mixture. How much of the 30% mixt

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Question 1042361: Please help me solve this mixture:
You need a 25% alcohol solution. On hand, you have a 20 mL of a 15% alcohol mixture. You also have 30% alcohol mixture. How much of the 30% mixture will you need to add to obtain the desired solution?
You will need
mL of the 30% solution
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
You need a 25% alcohol solution. On hand, you have a 20 mL of a 15% alcohol mixture. You also have 30% alcohol mixture. How much of the 30% mixture will you need to add to obtain the desired solution?
You will need ? mL of the 30% solution
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alco + alco = alco
0.15*20 + 0.30x = 0.25(20+x)
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15*20 + 30x = 25*20 + 25x
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5x = 10*20
x = 40 ml (amt. of 30% mixture needed)
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Cheers,
Stan H.
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