# A pharmacist wants to mix two solutions to obtain 100 cc of a solution that has an 8% concentration of a certain medicine. If one solution has a 10% concentration of the medicine and the second has a 5% concentration, how much of each of these solutions should she mix?

Question
Equations and inequalities
A pharmacist wants to mix two solutions to obtain 100 cc of a solution that has an 8% concentration of a certain medicine. If one solution has a 10% concentration of the medicine and the second has a 5% concentration, how much of each of these solutions should she mix?

2020-10-29
Let x be the amount of 10% concentracion so that 100-x is the amount of 5% concentracion, both in cc.
In terms of percentage, we write:
0.10(x)+0.05(100-x)=0.08(100)
Solve for x: 0.10x+5-0.05x=8
0.05x+5=8
0.05x=3
$$\displaystyle{x}=\frac{{3}}{{0.05}}$$
x=60
Hence, the pharmacist needs 60 cc of the 10% concentracion and 40 cc of the 5% concentracion.

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Suspect was Armed:
Black - 543
White - 1176
Hispanic - 378
Total - 2097
Suspect was unarmed:
Black - 60
White - 67
Hispanic - 38
Total - 165
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White - 1243
Hispanic - 416
Total - 2262
Give your answer as a decimal to at least three decimal places.
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b) What percent are Unarmed?
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Remember, the previous answer is only correct if the variables are Independent.
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If answer c is "significantly different" than answer d, then that means that there could be a different percentage of unarmed people being shot based on race. We will check this out later in the course.
Let's compare the percentage of unarmed shot for each race.
e) What percent are White and Unarmed?
f) What percent are Hispanic and Unarmed?
If you compare answers d, e and f it shows the highest percentage of unarmed people being shot is most likely white.
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g) What percent of blacks shot and killed by police were unarmed?
h) What percent of whites shot and killed by police were unarmed?
i) What percent of Hispanics shot and killed by police were unarmed?
You can see by the answers to part g and h, that the percentage of blacks that were unarmed and killed by police is approximately twice that of whites that were unarmed and killed by police.
j) Why do you believe this is happening?
Do a search on the internet for reasons why blacks are more likely to be killed by police. Read a few articles on the topic. Write your response using the articles as references. Give the websites used in your response. Your answer should be several sentences long with at least one website listed. This part of this problem will be graded after the due date.
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