In each of the following questions, four numbers are given. Out of these three are alike in some way but rest one is different. Choose the one which is different from the other.

Options

A. 21
B. 69
C. 81
D. 83

Answer

To solve the problem of identifying the odd number out of the given options, we can follow these steps:

### Step 1: List the given numbers
The numbers provided are:
- Option 1: 21
- Option 2: 69
- Option 3: 81
- Option 4: 83

### Step 2: Check divisibility by 3
We will check which of these numbers are divisible by 3.

- **For Option 1 (21)**:
- Calculation: 21 ÷ 3 = 7
- Result: 21 is divisible by 3.

- **For Option 2 (69)**:
- Calculation: 69 ÷ 3 = 23
- Result: 69 is divisible by 3.

- **For Option 3 (81)**:
- Calculation: 81 ÷ 3 = 27
- Result: 81 is divisible by 3.

- **For Option 4 (83)**:
- Calculation: 83 ÷ 3 = 27.67 (not a whole number)
- Result: 83 is not divisible by 3.

### Step 3: Identify the odd number
From our calculations, we see that:
- Options 1 (21), 2 (69), and 3 (81) are all divisible by 3.
- Option 4 (83) is not divisible by 3.

Thus, the number that is different from the others is **Option 4: 83**.

### Final Answer
The odd number out is **83**.

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