Question 396586
A chemist wants to dilute a 30% phosphoric acid solution to a 15% solution. He needs 10 liters of the 15% solution. How many liters of the 30% solution and water must the chemist use?

30% solution ------------- x liters
0%(water)-----------------------10-x liters
15%------------------------10 liters
...
30*x+0=15*10
30x=150 liters
/30
x= 5 liters of water.
5 liters of 30% solution
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