You are at a large international microbiology conference, having small talk with fellow researchers, when someone raises the famous old riddle:
"If, starting from one bacterium it will take a 100 time units to have a cup-full of bacteria, how long would it take to get a cup-full if we start with two bacteria?"
"50 time units!" you immediately say, trying to blend in the conversation (did I mention you are EXTREMELY shy, have a very hard time making small talk, and don't know anyone here?). You immediately realise the mistake you've made, everyone knows that the correct answer is 99 time units since bacteria usually replicate themselves every time unit.
You start getting weird looks, you think you hear someone murmur "how stupid" (or maybe it was "god bless you"?) someone says, "did you ever see an example for this?" and for some reason you say "yes!", and now there are follow-ups. "Elaborate?"
Quick! how do you explain why one bacteria creates a cup-full in 100 time units and two create it in 50?
Keep in mind the following:
- The number of new bacteria every time unit depends ONLY on the number of them in the previous unit.
- There's no such thing as a part-bacterium.
- The number of bacteria in a full cup is orders of magnitude larger than 1.