This week, I’m going back to the good ole engineering brainteaser. This one is for all you who have to fight to find a parking spot at work! The probability of finding the parking slot occupied is 1/3. You find it empty for 9 consecutive days. Find the probability that it will be empty on the 10th day. You can find this brainteaser and many others at GineersNow.com: Can You Answer These Brain Teasers Like a Silicon Valley Engineer?