Why does 9 × 9 = 81?

Because adding 9 9's together makes 81.

That is, because 9 + 9 + 9 + 9 + 9 + 9 + 9 + 9 + 9 = 81.

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Keep practicing
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Why does 9 × 9 = 81?

Because adding 9 9's together makes 81.

That is, because 9 + 9 + 9 + 9 + 9 + 9 + 9 + 9 + 9 = 81.

Keep practicing