The size-double lily pad patch Riddle

Hello, dear readers! Today I want to share with you a fun and easy riddle. But majority will  give wrong answer.

In a lake, there is a patch of lily pads. Every day, the patch doubles in size. If it takes 50 days to cover the entire lake, how long does it take for the patch to cover half of the lake? 

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 You might think that the answer is 25 days, but that's wrong. The trick is to work backwards from the end. 

Answer:
This is a classic example of an exponential growth problem.

If the patch covers the entire lake on day50, then it covers half of the lake on day 49. That's because on day 50, it doubles from half to full. So the answer is 49 days. Pretty simple, right? But wait, there's more!

What if I told you that you can use this problem to estimate how long it would take for a zombie apocalypse to wipe out humanity? Yes, you heard me right. Zombies are like lily pads, they multiply exponentially. Let's say that one zombie bites one person every day, and that person becomes a zombie the next day. How long would it take for the zombies to outnumber the humans?

Well, let's assume that there are 7.9 billion humans on Earth today. That means that on day 1, there is one zombie and 7.9 billion humans. On day 2, there are two zombies and 7.9 billion minus one humans. On day 3, there are four zombies and 7.9 billion minus three humans. And so on.

To find out how many days it takes for the zombies to outnumber the humans, we need to solve this equation and find the  smallest `x` such that:

`2^x > 7.9` billion, where `x` is the number of days.

Using a calculator or a logarithm table, we can find that x is about 33. So it would take only 33 days for the zombies to outnumber the humans! Scary, huh?

But don't worry, this is just a hypothetical scenario. There are no zombies in real life (as far as I know). And even if there were, we could always use our math skills to fight them off. After all, knowledge is power!

I hope you enjoyed this blog post and learned something new today. If you did, please like and share it with your friends. And don't forget to subscribe to my blog for more fun and easy math problems. Until next time, stay safe and happy!

- Ashan Jayamal -