Hi,
The answer is C) but cant seem to get the answer.... can you help??
How many liters of pure alcohol must be added to a 100-liter solution that is 20 percent alcohol in order to produce a solution that is 25 percent alcohol?
(A) 7/2
(B) 5
(C) 20/3
(D) 8
(E) 39/4
500 sc test6#19
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- jayhawk2001
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Let x be the amount of alcohol that needs to be added
(20+x) / (100+x) = 25 / 100
Solving for x, we get 20/3
(20+x) / (100+x) = 25 / 100
Solving for x, we get 20/3
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How many liters of pure alcohol must be added to a 100-liter solution that is 20 percent alcohol in order to produce a solution that is 25 percent alcohol?
(A) 7/2
(B) 5
(C) 20/3
(D) 8
(E) 39/4
100 liter solution which is 20% alchohol ; Thus it already has 20 liters of alchohol.
Suppose x litres must be added..
Now (20 + x / 100 + x)*100 = 25
2000 + 100x = 2500 + 25x
75x = 500
Thus x = 500/75 = 20/3 litres
Hope this helps!
(A) 7/2
(B) 5
(C) 20/3
(D) 8
(E) 39/4
100 liter solution which is 20% alchohol ; Thus it already has 20 liters of alchohol.
Suppose x litres must be added..
Now (20 + x / 100 + x)*100 = 25
2000 + 100x = 2500 + 25x
75x = 500
Thus x = 500/75 = 20/3 litres
Hope this helps!