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badatmath123
You need a 90% alcohol solution. On hand, you have a 110 mL of a 45% alcohol mixture. How much pure alcohol will you need to add to obtain the desired solution?
|dw:1337145943329:dw| it means that you require 10 parts of 45% solution and 45 parts of pure solution
I got the answer wrong, I got 500.5 mL of 100% alcohol added for a total of 611 mL of 90% alcohol.