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Eduardo86
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A six-liter solution is 85 percent alcohol. 06 Jun 2020, 04:27
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82% (01:50) correct 18% (01:58) wrong based on 298 sessions

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A six-liter solution is 85 percent alcohol. How many liters of pure alcohol must be added to produce a solution that is 90 percent alcohol?

A 0.6
B 1.0
C 2.1
D 3.0
E 5.4
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D
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A six-liter solution is 85 percent alcohol. 06 Jun 2020, 04:33
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Eduardo86
A six-liter solution is 85 percent alcohol. How many liters of pure alcohol must be added to produce a solution that is 90 percent alcohol?

A 0.6
B 1.0
C 2.1
D 3.0
E 5.4
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6*0.85+X=(X+6)*0.90
0.1X=6*0.05
X=3
D:)
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A six-liter solution is 85 percent alcohol. 06 Jun 2020, 04:52
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Eduardo86
A six-liter solution is 85 percent alcohol. How many liters of pure alcohol must be added to produce a solution that is 90 percent alcohol?

A 0.6
B 1.0
C 2.1
D 3.0
E 5.4
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Alchohol in existing solution + New alchohol added = Alchohol in Final Solution

i.e. \((\frac{85}{100})*6 + x = (\frac{90}{100})*(6+x)\)

i.e. \(85*6 + 100x = 90*6 + 90x\)

i.e. \(10x = 6*(90-85)\)

i.e. \(x = 3\)

Answer: Option D
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A six-liter solution is 85 percent alcohol. 06 Jun 2020, 08:58
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Eduardo86
A six-liter solution is 85 percent alcohol. How many liters of pure alcohol must be added to produce a solution that is 90 percent alcohol?

A 0.6
B 1.0
C 2.1
D 3.0
E 5.4
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given solution is 6 liters
alcohol % ; .85*6 ; 5.1
so as to make 90% alcohol we need to add

5.1+x/ 6+x = 90/100
solve for x = 3
OPTION D :)
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A six-liter solution is 85 percent alcohol. 12 Jun 2020, 06:23
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A six-liter solution is 85 percent alcohol. How many liters of pure alcohol must be added to produce a solution that is 90 percent alcohol?

A 0.6
B 1.0
C 2.1
D 3.0
E 5.4
Show more

Another approach could be :
Total = 6
Alcohol = 0.85*6 = 5.1, Other liquid = 6-5.1 = 0.9
The concentration of the other liquid will be 10% in new mixture,
so, total litres of new mix = 0.9/0.1 = 9 litres

therefore, Alcohol added = 9 -6 = 3
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A six-liter solution is 85 percent alcohol. 21 Oct 2020, 03:09
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90 - 85 / 100 - 90 = 5/10 = 1/2

90 is closer to 85; thus, 85 is more heavily weighted by a ratio of 2 : 1.

We have 6 liters, we need 3 liters of 100% to achieve 90%.
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A six-liter solution is 85 percent alcohol. 01 Nov 2024, 19:18
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