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A nurse is combining one solution with an 8% concentration of acid in
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07 Jun 2021, 05:00
07 Jun 2021, 05:00
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Question Stats:
88% (01:57) correct
12% (02:49) wrong based on 25 sessions
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A nurse is combining one solution with an 8% concentration of acid in water with another solution that has a 15% concentration of acid in water. If the nurse uses 120 ml of the 8% solution, what volume of the 15% solution should be used to obtain a mixture with 12% concentration?
Show: :: OA
160 ml
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Re: A nurse is combining one solution with an 8% concentration of acid in
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07 Jun 2021, 06:03
07 Jun 2021, 06:03
2
Carcass wrote:
A nurse is combining one solution with an 8% concentration of acid in water with another solution that has a 15% concentration of acid in water. If the nurse uses 120 ml of the 8% solution, what volume of the 15% solution should be used to obtain a mixture with 12% concentration?
Show: :: OA
160 ml
\(0.08x + 0.15y = 0.12(x+y)\)
\(8x + 15y = 12x + 12y\)
\(3y = 4x\)
\(y = \frac{4x}{3}\)
Given \(x = 120\),
So, \(y = \frac{4(120)}{3} = 160\)
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A nurse is combining one solution with an 8% concentration of acid in
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07 Jun 2021, 06:18
07 Jun 2021, 06:18
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We can use the mixture shortcut to solve this within seconds.
Conc. A has 8% acid, Conc. B has 15% acid, the mixture of both of them has 12% acid.
We just have to take the differences between 12% (the mixture) and each of concentration A and B, and assign the quotient to the other concentration (look at the figure above), to get the RATIO of Volume.
So we get the ratio of volume for 8% and 15% concentration as 3 : 4
Given, the nurse uses 120 ml of the 8% solution
So the volume of 15% conc. = (120/3) * 4 = 160 (Answer)
Hope this helps!
