Am I helping myself by using three numbers in a four-digit code?
There are 4! = 24 possible ways a password can be formed from four distinct and known numbers. Will using just three numbers increase the number of possibilities?
The surprising answer is that yes, it does.
You have two one-hour fuses: If you light one, it will be consumed in exactly one hour.Unfortunately, they’re badly made — some sections of each fuse burn faster than others. You know only that each full fuse will burn in one hour.Using only these two fuses and matches to light them, how can you tell when 45 minutes have passed?