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put this solution on YOUR website!how much pure alcohol must a nurse add to 10cc of 60% alcohol solution to strengthen it to a 90% solution?
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10 cc of 60% has 6 cc of alcohol in it and 4 cc of water.
To make it 90% by adding alcohol, the water will become 10% of the solution.
If 4 cc is 10%, the total is 40 cc.
40 - 10 = 30 cc of added alcohol
