Last Friday night, while the rest of the world was lining up to see The Avengers, I took my daughters to see The Pirates! Band of Misfits. Our hero, The Pirate Captain, desires to win the Pirate of the Year Award. He explains to his rag-tag crew, “Every time I’ve entered I’ve failed to win, so I must have a really good chance this time.” The gambler’s fallacy! In a children’s movie, no less. [The gambler’s fallacy is the belief that previous failures indicate an increased probability of success on subsequent attempts. It’s why I renew my (share of) Canucks season tickets every year.]
Fast-forward to Tuesday, lunch. I’m in the line-up to pay for my fish taco when I spot this¹:
I immediately ask myself, “How many Rice Krispies is that?” Other (more interesting?) questions soon follow:
- “What size of Rice Krispie square could you make with these?”
- “How many big marshmallows would I need to make this giant Rice Krispie square?”
- “How many calories would that be?”
- “How many ‘Snap, Crackle, Pops’ could I expect from 22 lbs of Rice Krispies?”
These sequels/extentensions offer more than “How many Rice Krispies are there in 50 kg?” In addition to proportional reasoning, there are connections to volume and probability.
I’ll upload this to 101questions. I’m curious if other math teachers will find it perplexing but that’s not really what’s important to me. What is important is that I’m starting to see math everywhere.
I blame Dan Meyer.
¹ From ages 15 to 24 I worked as a grocery clerk at Safeway. Sometime during a new hiree’s first shift, we’d ask him to run and do a price check on some seemingly mythical item such as pork wings, ice mix, or a 20 kg bag of puffed wheat. Huh. Who knew?