Roll Number Rule Analysis

The question asks us to identify the roll number that does not follow the specific rule provided.

Rule Identification

The rule is stated as: Last 3 digits = First 3 digits + 100. We need to test each roll number against this rule.

Option Analysis

Let's analyze each roll number, represented as $XXXKYYY$, where $XXX$ are the first three digits and $YYY$ are the last three digits.

• Option 1: 200K300
  • First 3 digits (XXX): 200
  • Last 3 digits (YYY): 300
  • Applying the rule: Is $300 = 200 + 100$? Yes, $300 = 300$. This roll number fits the rule.
• Option 2: 150K250
  • First 3 digits (XXX): 150
  • Last 3 digits (YYY): 250
  • Applying the rule: Is $250 = 150 + 100$? Yes, $250 = 250$. This roll number fits the rule.
• Option 3: 250K350
  • First 3 digits (XXX): 250
  • Last 3 digits (YYY): 350
  • Applying the rule: Is $350 = 250 + 100$? Yes, $350 = 350$. This roll number fits the rule.
• Option 4: 100K250
  • First 3 digits (XXX): 100
  • Last 3 digits (YYY): 250
  • Applying the rule: Is $250 = 100 + 100$? No, $250 \neq 200$. This roll number does not fit the rule.

Conclusion

The roll number 100K250 is the one that does not follow the rule that the last 3 digits must equal the first 3 digits plus 100.