A system error causes the change of John's net banking password. To sort this out, he calls the customer care. The following is the conversation he had with the executive:
John: My password has been changed.
Custom Care Executive: We have kept your password distinct this time. It has 8 letters out of which, 3 letters are the same as the previous one.
John: Okay, thanks.
Can you determine the old as well as the new password of John's net banking account after reading the conversation carefully?
Samuel was out for a walk when it started to rain. He did not have an umbrella and he wasn't wearing a hat. His clothes were soaked, yet not a single hair on his head got wet. How could this happen?
A man was gazing through the window of the 23rd floor of the building. He suddenly opened the window and jumped on the other side of the window. On landing on the floor, there was not a sheer mark of injury on him.
How can that be possible if he did not use any kind of parachute and did not land on a soft surface?
You are camping with your friends. You have a flashlight for any emergency and have brought 8 batteries along with you. Your brother calls to tell you that four of those batteries are already dead.
Your flashlight requires two working batteries to run. What is the least number of pairs you will need to test to guarantee that you can get the flashlight on?