1. Data Collection, Probability, and Inventory

2. School T-shirts Tacos Cars Coffee What data do we collect?
Color
Size
Tacos
Chicken, pork, or carne asada
Flour or tortilla
Cars
3 different make or 3 different model
Coffee
Flavor or type of coffee
Note to Teacher: Have students discuss each product and what possible data to collect before you tell them. Teacher says, “What data should I collect if I were to sell school t-shirts?” Answers may vary. Discuss and then tell them that color and size is one example. Repeat the process with the other products.

3. Data collection Who should we survey (sample)? Confidence Level
Population size: Determine what your whole population size is. Your population is the entire set of people you want to study with your survey.
Confidence Level
How accurately your sample represents your population
Ex: 95% confidence level means that you would get the same results 95% of the time even if you chose different samples from the population.
Standard confidence level is 95%.
Degree of Accuracy
How sure you want to be that the responses you get will accurately represent the views of the population.
Standard degree of accuracy is 5%.
Teacher says, “In our ice cream business, we sampled (surveyed) 100 students. We used 100 students because we were restricted with time. Researchers have a formula that they use to ensure that they have a high confidence level and high degree of accuracy.”
Go through each bullet point and have students take notes. Have students fill in cloze procedure notes (handout).
Tell students that they will not have to find this number. Instead (since this is not a statistics class) they will be using the chart given to determine the sample size using the standard confidence level and degree of accuracy. Give student Sample Size chart and model to students how to use it.

4. What do we do with the data? Why?
Use probabilities from data to determine how much inventory to purchase
Help him decide on a reasonable distribution of inventory
Minimize stagnant inventory
Discuss/review the term reasonable distribution with students. Have students pair-share what this terms means and why it is important.
“It is crucial that businesses have reasonable distribution of inventory for many reasons. Please discuss with your partner and come up with one reason why it would be important.”
Solicit student answers.
Answers should include: 1) too much inventory: stagnant inventory. Cash flow is used on inventory that is not being sold. That cash could be used for other inventory that the business may need, or to benefit the business in another way, or as profit!
2) too little inventory: losing on profit because customers want to purchase, but there is not inventory

5. How much inventory? 15 25 16 56 6 5 26 11 2 18 51 23 100 Example:
Beanies
Small
Medium
Large
Total
Black 15 25 16 56
Blue 6 5 26
Pink 11 2 18 51 23
100
Work through example with students.
“What is the probability of a customer buying a black beanie?” Student gives the correct answer of 56% or 14/25. “Therefore, 56% of inventory should be black beanies.
Work through as many examples as needed until students are proficient in concept.