Question 230583
If 800 ml of a juice drink is 15% grape juice, how much grape juice should be added to make a drink that is 20% grape juice?
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The other 85% is water = 800*0.85 = 680 ml of water.
Add juice to make that 680 ml of water 80% of the solution.
If 680 ml is 80%, then the total solution is 680/0.8 = 850 ml
--> add 50 ml of juice.