What is 0.9 repeating as a rational number?

= 1 — the sequence of terminating decimals 0.9, 0.99, 0.999, 0.9999, and so on, converges to 1, so the repeating decimal 0.9999... representing the limit of that sequence, is said to be equal to 1. The same idea works for any rational number with a repeating infinite decimal expansion. 0.333.

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