Each of the two positive integers a and b ends with the digit 2 . With what number does a - b end?

Answer

To solve the problem, we need to determine the last digit of the result when we subtract two positive integers \( a \) and \( b \), both of which end with the digit 2.

### Step-by-Step Solution:

1. **Identify the last digit of \( a \) and \( b \)**:
- Since both integers \( a \) and \( b \) end with the digit 2, we can express them as:
\[ a = \text{...2} \quad \text{and} \quad b = \text{...2} \]
- Here, "..." represents any digits before the last digit.

2. **Perform the subtraction \( a - b \)**:
- We focus on the last digits of \( a \) and \( b \):
\[ a - b = \text{...2} - \text{...2} \]

3. **Subtract the last digits**:
- The last digit of \( a \) is 2 and the last digit of \( b \) is also 2. Therefore, we calculate:
\[ 2 - 2 = 0 \]

4. **Determine the last digit of \( a - b \)**:
- Since the last digit of the result \( a - b \) is 0, we conclude:
\[ a - b \text{ ends with the digit } 0. \]

### Conclusion:
Thus, the number \( a - b \) ends with the digit **0**.

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