Everyone has typos.
That’s not what we are dealing with.
Not too long ago I encountered a high school student working the register at a Whataburger drive thru who didn’t know how to make change ... because I had given a few cents extra to get an even dollar back. He had to call over his manager whose expression, as she realized the problem, was one of complete dismay.
And despite her efforts he still didn’t give the correct change ... and it was so sad that I just cut my losses.
I went to a McDonalds after a volunteer rodeo shift one night 3 or 4 years ago. The computers were down, so the high schooler at the window didn’t know how much I owed. I told it’s simple, take the total, multiple it by 1.0825 (the tax rate is 8.25%), and whatever that is is what I owe. She said she didn’t have a calculator. I asked if she had a cell phone, which has a calculator app on it by default. She was shocked I knew how to figure out the exact amount I owed.
Common sense, ain’t.