A 25—ounce solution is 20 percent alcohol. If 50 ounces of water are a

Question

A 25—ounce solution is 20 percent alcohol. If 50 ounces of water are added to it, what percent of the new solution is alcohol?

A. 5%
B. 20/3%
C. 8%
D. 10%
E. 20%

gracie · Answer

let x=% alcohol of new solution
.2*25=x*(25+50)
x=1/15=20/3%
B

Archit3110 · Answer

25*20/100 = 5 ounce alchol

now 50 ounces is added 
so 5/75 = 6.66% or 20/3% IMO B

CrackverbalGMAT · Answer

Amount of alcohol in the 25 ounce, 20% alcohol solution = 25 * 0.2 = 5 ounces

When 50 ounces of water are added, the total solution = 25 + 50 = 75 ounces

The question is now what is the % of alcohol in the solution.

Percentage = \frac{5}{75} * 100 = \frac{20}{3} %

Another way to think about this is that if 25 ounces of water were added, that is if the amount of solution is doubled, then the % of alcohol is halved.  \frac{5}{50}* 100  = 10%

Now we are adding 50 ounces of water, that is we are increasing the volume of the solution 3 times, therefore the % of alcohol is 1/3 rd the original % =  \frac{20}{3} %

Option B

Arun Kumar

A 25—ounce solution is 20 percent alcohol. If 50 ounces of water are a

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A 25—ounce solution is 20 percent alcohol. If 50 ounces of water are a

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