Why does 7 x 3 = 21?

Because adding 7 3's together makes 21.

That is, because 31 + 32 + 33 + 34 + 35 + 36 + 37 = 21.

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Why does 7 x 3 = 21?

Because adding 7 3's together makes 21.

That is, because 31 + 32 + 33 + 34 + 35 + 36 + 37 = 21.

Keep practicing