What happens when you show up on Friday night at your favorite diner with a group of friends and realize you are #10 on the waiting list? You could walk out and go elsewhere but nobody has better grilled cheese and chocolate cheesecake OR you could treat it as a math problem and try and come up with an estimate of how long the wait is going to be. You count all the tables in the diner (15 or so) and figure that most meals here take about 45 minutes to complete (they like to turn their tables:) Your friends then turn to you and ask "Ok math genius, how long do you think we will have to wait?"

Ask your students to estimate how long the wait will be in this scenario (#10 on wait list, diner with 15 tables and 45 minutes per meal; this is the BASE CASE): 

Then use this simulation to see how well they did (I recommend using the FAST button):

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Have your students try these scenarios too to see how their wait times might vary:

1. What if the average meal time was an hour? Would that add 15 minutes to their wait time? Compare your results.
2. What if there were 25 tables at the restaurant? How much would that improve your wait time from the Base Case? 
3. Is there another variable that isn't captured here that could also have a big impact on your waiting time?

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Looking for more ways to infuse math into your personal finance course. Check out NGPF Data Crunches!

About the Author

Tim Ranzetta

Tim's saving habits started at seven when a neighbor with a broken hip gave him a dog walking job. Her recovery, which took almost a year, resulted in Tim getting to know the bank tellers quite well (and accumulating a savings account balance of over $300!). His recent entrepreneurial adventures have included driving a shredding truck, analyzing executive compensation packages for Fortune 500 companies and helping families make better college financing decisions. After volunteering in 2010 to create and teach a personal finance program at Eastside College Prep in East Palo Alto, Tim saw firsthand the impact of an engaging and activity-based curriculum, which inspired him to start a new non-profit, Next Gen Personal Finance.

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