NA: Divisibility

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Divisibility Rule: Factoring by 3
Let n ∈ ℤ. n is divisible by 3 or 3∣n or n ≡ 0 (mod 3) if the sum of the digits of n is divisible by 3.

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Let n ∈ ℤ. n is divisible by 4 or 4∣n or n ≡ 0 (mod 4) if____

Let n ∈ ℤ. n is divisible by 5 or 5∣n or n ≡ 0 (mod 5) if _____

Divisibility Rule:
Let n ∈ ℤ. n is divisible by 6 or 6∣n or n ≡ 0 (mod 6) if ______

Divisibility Rule:
Let n ∈ ℤ. n is divisible by 7 or 7∣n or n ≡ 0 (mod 7) by step 1,2,3. What are those steps?

Divisibility Rule:
Let n ∈ ℤ. We say that n is divisible by 8 or 8∣n or n ≡ 0 (mod 8) if _____

Divisibility Rule:
If n is divisible by both 3 and 4. Then n is divisible by

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Divisibility Rule:
if the difference of the sum of digits at the odd and even places is equal to 0 or 11, then the number is divisible by ____

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Divisibility Rule:
Let n ∈ ℤ. We say that n is divisible by 10 or 10∣n or n ≡ 0 (mod 10) if the the last digit of n is

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