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A nurse has 80 ml of a solution that has a concentration of 5% Drug X
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23 Mar 2021, 05:49
23 Mar 2021, 05:49
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A nurse has 80 ml of a solution that has a concentration of 5% Drug X in water. How many milliliters of pure water containing none of the drug must the nurse add to dilute the concentration to 2% Drug X in water?
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Question part of the project GRE Quantitative Reasoning Daily Challenge - (2021) EDITION
GRE - Math Book
Show: :: OA
120 ml
Kudos for the right answer and explanation
Question part of the project GRE Quantitative Reasoning Daily Challenge - (2021) EDITION
GRE - Math Book
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A nurse has 80 ml of a solution that has a concentration of 5% Drug X
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23 Mar 2021, 08:40
23 Mar 2021, 08:40
Carcass wrote:
A nurse has 80 ml of a solution that has a concentration of 5% Drug X in water. How many milliliters of pure water containing none of the drug must the nurse add to dilute the concentration to 2% Drug X in water?
Show: :: OA
120 ml
Let us make an equation for the Water:
95%(80) + W = 98%(80 + W)
\(76 + W = 78.4 + 0.98W\)
\(0.02W = 2.4\)
\(W = 120\)
General Discussion
Re: A nurse has 80 ml of a solution that has a concentration of 5% Drug X
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23 Mar 2021, 06:51
23 Mar 2021, 06:51
2
80 ml of a solution that has a concentration of 5% Drug X in water.
So, Drug X = 80 * 0.05 = 4 ml
This 4 ml needs to be 2% in the new solution.
So, the new solution will be = 4 /0.02 = 200 ml
Finally, the amount of water needed = 200 - 80 = 120 ml
So, Drug X = 80 * 0.05 = 4 ml
This 4 ml needs to be 2% in the new solution.
So, the new solution will be = 4 /0.02 = 200 ml
Finally, the amount of water needed = 200 - 80 = 120 ml
