Look at the image below: This image is about weather forecast. It says about chance of rain during coming few hours of the day in the city. Look at the number 30% at 7 AM. It means that there is 30% chance of rain at that time. In other words, probability of rain at that time is 0.3. It gives you some idea but can you conclude anything from this? You can expect to have rain on 3 occasions out of 10 with similar conditions and forecast. Mind it, you expect only. You are not sure. In fact, you will get rain on other than 3 occasions out of 10 more frequently than 3. Probabilistic situation is like that. It deals with uncertainty.  Let us understand this with some easier situation. Take 10 cards of same size and look, and write 'rain' on 3 cards. Write 'no rain' on remaining cards. Shuffle these cards properly and randomly select a card from this pack. What would you get? You can get any of the two 'rain' or 'no rain'. But you expect more to get 'no rai

During morning walk, I saw a bench on the right side of the path, something like below image. As I walked further, I found another bench but on the left side of the path. Something like below image. I found that these benches were placed at some regular intervals. There were few places on the path with benches on left side and right side both. I found this quite interesting and useful. Persons walking on the path get place to sit and relax at some intervals with views of right side or left side. Whereas, there are places where people can sit in front of each other and relax.  I decided to get some idea about the distance between two consecutive benches on either sides of the path. I counted the number of steps required to move from one bench to other and got estimates of intervals between two consecutive benches. Left side benches were placed at interval of 200 meters whereas right side benches were 140 meters apart.  There can be several interesting questions in this scenario. You hav