## I Entertain Myself with Mathematics at the Supermarket

Like many engineers, I sit on my backside for hours and hours every day. It’s a real challenge to get any exercise at all. On weekends, if the weather is nice (which doesn’t happen all that often in the Seattle area) I’ll sometimes walk the 1.5 miles to my local QFC grocery store. I usually go early in the morning.

This past Saturday was the 4th of July weekend. I walked to QFC and entertained myself with mathematics in the Bakery department. The first sign I noticed was at the cupcake and brownie display area. The brownies were \$2.99 for about nine. OK, makes sense. But the cupcakes were \$28.03 for a package of eight rather average looking cupcakes. I thought to myself, “Wow, those must be pretty special cupcakes.” It took me a couple moments to figure out that the \$28.03 was the price of the table the cupcakes were sitting on. (I’m still not sure why the price is \$28.03 instead of \$28 — that extra three cents must make a difference somehow).

Then I moved on to the pie display area. I saw that the fancy “cherry-peach-blueberry” flavored pies were on sale for \$6.99 each. I love pies. I’ve had semi-exotic flavors of pie, like strawberry-rhubarb, before and like them, so I thought I’d buy one of these fancy cherry-peach-blueberry pies. I looked and looked but I couldn’t find one in that flavor. “Darn,” I thought, “They must be sold out.” It wasn’t until I got home that I figured out the sign meant cherry OR peach OR blueberry, instead of cherry AND peach AND blueberry. Sigh. Applying faulty Boolean logic to the pie sign was my downfall. Do not send a math person to buy a pie.

Next, I strolled by the department where they make and decorate custom in-house cakes. I noticed the sign that read, “Friendly Bakery Associates Available 6 AM – 7 PM”. I asked the guy and the girl what would happen before 6:00 AM or after 7:00 PM. They explained that during those times, the Unfriendly Bakery Associates were on duty.

Just joking of course. I asked the guy and the girl to act angry and shake their fists at me so I could take a photo for this blog post. So they pretended to be angry. Well, at least I’m pretty sure they were pretending.

There’s entertaining mathematics everywhere.