The Divisibilty Rule for 3: A number is divisible by 3 if the sum of the digits is divisible by 3.

What does this mean? This means that we need to add up the digits in the number and see of the answer is can be divided by 3 without a remainder.

Example: 34,911

Step 1: Add up the digits. 3 + 4 + 9 + 1 + 1 = 18

Step 2: Determine if 3 divides evenly into the sum of 18. Yes, 3 x 6 = 18. So 3 goes evenly into 18.

Step 3: Use the result to determine if 3 goes into 34,911. Because 3 divides into 18 evenly, 3 also divides evenly into 34,911. So 3 is a factor of 34,911.

Example: 45,799

Step 1: 4 + 5 + 7 + 9 + 9 = 34

Step 2: 3 does not divide evenly into 34.

Step 3: Therefore, 3 also does not divide evenly into 45,799. So 3 is not a factor of 45,799.

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