Why does 10 + 3 = 13?

Let's start at 10.

Next, let's count 3 times.

Ready? ... 10, 111, 122, 133.

That's why 10 + 3 = 13.

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Keep practicing
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Why does 10 + 3 = 13?

Let's start at 10.

Next, let's count 3 times.

Ready? ... 10, 111, 122, 133.

That's why 10 + 3 = 13.

Keep practicing