Below, you will find the mathematical proof that 10 equals 9.99999. But is that possible or there is something wrong about it? Can you find the error?

x = 9.999999...
10x = 99.999999...
10x - x = 90
9x = 90
x = 10

Mathematical Proof Puzzle

No error is present in this proof and 10 is actually equal to 9.99999. The proof is absolutely correct.

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