Summer 2015
Social Justice and Mathematics Review
Day #4: Additional Explorations
Situation I: Can You Believe Everything You Hear?
At the conclusion of a recent fiscal year for welfare calculations, two politicians made the following claims, based on data from the fiscal year:
Pat Lysander:
“During any week of the fiscal year, at least 90% of active welfare recipients were those who received benefits throughout the entire year.”
Kelly Horshilman:
“At least 85% of those who received welfare benefits during the fiscal year were on welfare for only a week.”
Pat was referring to long-term welfare recipients and Kelly described short-term welfare recipients.
- What might have been the intentions of each of these politicians in making these statements?
- Explore these claims. Could they both be true?Devise a scenario that will help you explore the mathematics of these claims in order to refute or support the possibilities.
- Discuss the significance of the mathematics used throughout this activity.
- What additional issues and questions emerge from this activity?
Situation II: Any Differences?
Twin sisters, Gymane and Lynette, shared many attributes, but one in which they differed was their attitude and behavior toward saving for the future.
When Gymane was 20 years old, she had just completed a course that included information and activities describing calculations of compound interest. She was so strongly influence by what she had learned that at 20 years of age, she committed to saving money on a regular basis.
She scratched and saved in order to salt away $2500 each year. Starting on her 21st birthday, Gymane deposited this amount into a savings account and continued such deposits for a total of 10years (through her 30th birthday). She made no withdrawals from her account and she kept all interest earned in the account. After 10 years, she simply left the account grow in value without making any additional deposits.
Gymane spoke to Lynette frequently about saving money for the future, but Lynette didn’t have a savings plan. Instead, she tended to spend everything she earned. But Gymane persisted, and when Lynette celebrated her 31st birthday, she finally started saving. Each year on her birthday, she deposited $2500 into a savings account. She let the interest grow in the account and made no withdrawals.
- Acting like you are a student who is not familiar with any memorized compound interest formulas,
- Identify the variables in this situation.
- Make comparisons about the results of the sisters’ savings plans.
- Discuss the significance of the mathematics used throughout this activity.
- What additional issues and questions emerge from this activity?
- What supplementary problems might you ask a high school class following these two activities (Situation I and/or II)?