I was driving with two friends, entering the inner-city tollway, which costs Rp 4500. Eriz, Ms Initiative, gave me Rp 5500 so it would be easier for the toll booth guy to give change in Rp 1000, rather that the often-scarce-when-needed Rp 500 coin. So it was one Rp 5000 bill and one Rp 500 coin.
Of course, Mr Toll Booth Guy, with years of training and experience giving change to a thousand cars a day, saw the Rp 5000 bill from afar and prepared Rp 500 change.
I gave the Rp 5500 anyway to Mr Toll Booth Guy, and at one point he gave me only Rp 500 change when it should be Rp 1000. But then I showed him the Rp 500 coin, prompting him to take the coin, and give me back Rp 1000's worth in the form of two Rp 500 coins.
So... here's the question. Who was stupider, me, Eriz, or Mr Toll Booth Guy?