Yeh... this won't work.

First of all: < 49 = Result lower than 49 wins. > 51 = Number higher than 51 wins. You seem to switch them.

Secondly if I want to get a result lower than 49, obviously I would just select a number 0-4. Why would I ever chose 5-9?

And because of that I got a huge advantage over the casino.

However, the casino can still easily cheat too. They can just generate a number 0-4 always when I click "over 51". How do you know that this 0-4 number was fairly generated? You cannot know that and you would

**lose literally every bet**. So that is not provably fair.

The basics of provably fair aren't that difficult. Simple example:

Casino generates number + protects it with secret and makes a hash for it. You might find the hash confusing.. but the idea is that the casino gives "their result" in advance.. so they cannot modify it anymore. But it is hashed otherwise you know the end result in advance and could cheat.

sha256(43-xh7MB8GtqgLmiScbaohDzL2iUoADZhIeyxMabhlX)

Hash that you get in advance:

21aa12583439f7fd78e3e8630129c146edabbdbf0fa22a2e0cf48b49609828c9

Now you make your bet and send in your result, let's say 76 and "over 51". Casino reveals their number+secret. You can check that the hash was really from that number+secret with any

online SHA256 generator.

**So you can prove that the casino didn't change their number.** (This is missing from your idea.)

For the number generation, they would just add up the numbers and if its over 100 remove 100 from it, so (76+43) = 119 - 100 = end result 19. Since you bet "over 51" you lose.

With this you proved: 1) the casino calculated the result with THEIR and YOUR input so neither party could know the end result in advance 2) the casino didn't change THEIR input since you had the hash BEFORE you gave YOUR input.

This is a simplified idea. The average "per roll implementation" and even the "nonce implementation" are based on the same idea with just a bit different result generation. IMO the nonce implementation is the best for individual betting because you don't need to verify the hash literally every bet. You can see a more detailed but still practical explanation about that here:

https://dicesites.com/provably-fair