Being short $10 dollars

Sometimes, peoples’ lack of maths skills amaze me.

I was at the airport the other night, buying some stuff.

Total cost $41.35.

Gave the old bloke $60 (3 x $20).

I received $28.65 change, a “bonus” of $10.

Spent the next five minutes arguing with the old bloke, that he was short-changing himself [...]