Human beings are annoying

I think it's long overdue that I have a rant about customers. I mean, some of these people are so stupid and annoying!! For example:

Me: That's 16 dollars.
Customer: -hands me 50 dollar note-
Me: Thanks, thats 34 dollars change
Customer: -blank stare- You said it was fifteen dollars -accusing voice-
Me:....Oh sorry well I meant 16.
Me thinking in head: No, I definitely said 16 you stupid customer.

And that one doesn't actually sound that bad, but it's just an example of the many examples. However, I had another one today as well:

Customers total was 46.22.
Me: thats 46.20
Customer: Can I pay half on my card and half in cash? (I'm actually used to customers doing that though) -hands me 23.20-
Me: -puts cash through on computer- Okay so the rest on your card?
Customer:.....Do you think you can put the amount on my card through first? Because if you put it through at 23.20 then when I pay cash the amount will be rounded down and I'll save two cents.
Me:.....Well its kinda too late...
Customer: -irritated look on face- Oh okay then......

I mean, TWO cents. She was trying to save TWO cents. I almost threw the receipts at her.


.....Although, sometimes I make mistakes too......

Customer: -hands me rather large yellow citrus fruit-
Me:.......Um is this a lemon or a grapefruit?
Customer: -gives me weird look- It's an orange....
Me: -_-''

Oops.