SOLUTION: A chemist needs 45 liters of 35% acid solution. She has containers of 20% solution and 75% solution. She needs to combine liters of 20% solution and liters of 75% solution to hav

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Question 680392: A chemist needs 45 liters of 35% acid solution.
She has containers of 20% solution and 75% solution.
She needs to combine liters of 20% solution and liters of 75% solution to have 45 liters of 35% acid solution.
Round each value to one decimal place.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
chemist needs 45 liters of 35% acid solution.
She has containers of 20% solution and 75% solution.
She needs to combine liters of 20% solution and liters of 75% solution to have 45 liters of 35% acid solution.
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Equation:
acid + acid = acid
0.20x + 0.75(45-x) = 0.35(45)
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Multiply thru by 100 to get:
20x + 75*45 - 75x = 35*45
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-55x = -40*45
x = (8/11)45
x = 32.73 liters (amt. of 20% solution needed)
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45-x = 12.27 liters (amt. of 75% solution needed)
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Cheers,
Stan H.
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