Basic Trig and Algebra are everywhere....
I was in the Target store the other day. The young, white male cashier had a bit of a problem and asked a middle-aged black worker nearby a question. Had something to do with change on a $2. purchase.
I sensed it had something to do with counting change or the like. I looked over at the gal, kind of rolled my head and smiled. She grinned and rolled her eyes. It was funny.