Doha Intercontinental Hotel Oktoberfest tickets cost QAR 170 each. I was buying two, from hotel reception, for which I handed over QAR 350, not having the exact change. The receptionist, as upright and smart-suited a young man as one would expect in a five-star establishment, placed my money and tickets carefully out of reach below the counter and proceeded to walk the considerable length of reception to borrow a calculator from the cashier. On returning, he entered the following calculation: 170 x 2 = 340. So far, so good. He then took a notepad and pen and wrote down the number 340. Next, he cleared the calculator display and performed a new calculation, 350 - 340 = 10. Returning to his note pad, he wrote the number 10. He looked up at last and explained to me: "You have purchased two tickets at 170 each. That totals 340. You have given me 350, so your change will be 10 Riyals. Please step this way to the Cashier desk to complete the transaction". And when the cashier'