Do you remember when you were young and after solving a simple equation you had to check that your answer was correct? Say you solved x + 3 = 7. You found the answer is 4. But you could also check it by doing 4 + 3 and seeing if it equals 7.
> What kind of math problems are they solving?
They are checking answers that they guess to an equation that is otherwise unsolvable by natural means because it cannot be reversed.
Like in the above solution they would try random numbers like 10, 7, 1, 21 until eventually you’d stumble upon 4 and realize it’s a solution.
Whoever finds an answer that checks the solution first is considered the winner. The fact that they found it means that some transactions are considered accepted. Everyone else can check that the answer they found is correct so they move on to finding the next lucky number. That means they have mined something.
As someone else said in their comment, they are basically guessing lottery numbers. The more lucky numbers you can check, the more chances you have for being the lucky winner.
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