#### Cooldefekt

##### New member

- Joined
- Jan 2, 2022

- Messages
- 5

Sorry if this riddle post is in wrong category, first time here and little time since I got interested in math.

But lets write a math riddle that got me hook since I first heard it and I know its all math behind its solution:

Interesting mathematics:

In a lake there is just one fish in the begining. That fish spawn(produce) for the first time one fish egg on the seventh day and after that on every 6th day. Every new fish spawn the same way, for the first time on seventh day and after on every sixth day. How to find how namy fish there will be in 80 days( taking account the spawning of the first fish and all the others)?