Why does 4 + 5 = 9?

Let's start at 4.

Next, let's count 5 times.

Ready? ... 4, 51, 62, 73, 84, 95.

That's why 4 + 5 = 9.

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Keep practicing
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Why does 4 + 5 = 9?

Let's start at 4.

Next, let's count 5 times.

Ready? ... 4, 51, 62, 73, 84, 95.

That's why 4 + 5 = 9.

Keep practicing