Which of the following numbers are divisible by 3?
182,391

Answer

To determine which of the given numbers, 182 and 391, are divisible by 3, we will use the divisibility rule for 3. According to this rule, a number is divisible by 3 if the sum of its digits is divisible by 3.

### Step-by-Step Solution:

1. **Identify the digits of the first number (182)**:
- The digits are 1, 8, and 2.

2. **Calculate the sum of the digits of 182**:
- Sum = 1 + 8 + 2 = 11.

3. **Check if the sum (11) is divisible by 3**:
- To check divisibility, divide 11 by 3.
- 11 ÷ 3 = 3 remainder 2.
- Since there is a remainder, 11 is not divisible by 3.

4. **Conclusion for 182**:
- Since the sum of the digits (11) is not divisible by 3, **182 is not divisible by 3**.

5. **Identify the digits of the second number (391)**:
- The digits are 3, 9, and 1.

6. **Calculate the sum of the digits of 391**:
- Sum = 3 + 9 + 1 = 13.

7. **Check if the sum (13) is divisible by 3**:
- To check divisibility, divide 13 by 3.
- 13 ÷ 3 = 4 remainder 1.
- Since there is a remainder, 13 is not divisible by 3.

8. **Conclusion for 391**:
- Since the sum of the digits (13) is not divisible by 3, **391 is not divisible by 3**.

### Final Answer:
Neither 182 nor 391 is divisible by 3.

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