1. February homework
Math 123, Spring 2019

2. What do we know about the water crisis in
Flint, Michigan?

3. Video: Lead Found in Tap water in Flint, MI (1:32 min)

4. The Washington Post reported that there is a water emergency in the city of Flint, Michigan. Scientists found elevated levels of lead (which is poison) in Flint’s water supply. Blood tests revealed that lead contamination had nearly doubled and tripled in children younger than 5 who were exposed to the highest lead levels. The water is undrinkable.

5. Corporations Give Water to Flint, MI
Walmart, Coca Cola, Nestlé, PepsiCo said that they will donate bottles of water for school children in Flint, Michigan, to help with the city’s public health crisis over lead contaminated water.
On January 26, 2016 the companies said that they are planning to “collectively donate water to meet the daily needs of over 10,000 school children for the balance of the calendar year.” To do so, the companies will send 176 truck loads of bottled water – up to 6.5 million bottles – to Flint.
How do we know how much water would be enough to meet the "daily needs" of Flint school children until December 31, 2016?
Is the companies’ plan a good one?

6. A Public-health Emergency: Is this enough water for the children?
Goal: Come up with a mathematical model to answer the questions from the previous slide.
Materials: You are allowed to look up any information you think will help you solve the problem.
What to turn in:
Work on paper. Present your mathematical model and show all assumptions you made and calculations you performed. Clearly state your conclusion. Your work should be similar to the work you did on the car wash problem. Make sure to show a sufficient amount of math.
Note that there are other parts to turn in. The last slide will summarize all questions you will have to answer.

7. Statement of the Problem Conclusions and Validity
Include the following in your solution (your choice of arrangement)
Statement of the Problem
What is the problem we are solving?
Information Needed
What information do we need?
Assumptions
What decisions will we make?
The Model
Include equations, diagrams, descriptions
Computation
Use the model to compute
Interpretations
What does the solution mean?
Conclusions and Validity
Does the solution make sense?
Is the solution reasonable?
What conclusions can we draw?
Refining the Model
Do we need to re-think our assumptions?
What are other possible methods to solve this problem?
How do alternate methods impact our existing model?
Recommendations
What recommendations do we have for the corporations?

8. Other Social Issues
The Flint, Michigan Water Crisis is a serious social issue that has impacted the children and adults of the community in negative ways.
Questions to consider:
What about the families of the school children?
What about the environmental waste of plastic 1-L bottles. How much can we reduce the plastic waste by delivering 1.5-L bottles instead?
An article indicated that an ID would be required of the Flint residents to receive water. What about undocumented residents who cannot show an ID to receive water? According to there are approximately 1000 undocumented people in Flint, MI.
To turn in: How could your model be modified to account for some of these issues, and possibly others?

9. Standards for Mathematical Practice
1. Make sense of problems and persevere in solving them
2. Reason abstractly and quantitatively
3. Construct viable arguments and critique the reasoning of others
4. Model with mathematics
5. Use appropriate tools strategically
6. Attend to precision
7. Look for and make use of structure
8. Look for and express regularity in repeated reasoning
Full text here:
To turn in: Which standards for mathematical practice did you engage with in this problem and how?

10. Summary of questions to answer
How do we know how much water would be enough to meet the "daily needs" of Flint school children until December 31, 2016? Show all assumptions and calculations. (See slides 5 and 6)
Is the companies’ plan a good one? Show all assumptions and calculations. (See slides 5 and 6)
How could your model be modified to account for some of the additional issues, either the ones mentioned or others that you are curious about? (See slide 7)
Which standards for mathematical practice did you engage with in this problem and how? (See slide 8)
Reflection:
What else would you like to know about the Flint water crisis?
What other mathematical questions could we pose about the Flint water crisis?
What are the benefits of and challenges to using problems like these in K-12 math classrooms?