Source-of-truth checkpoint

Your task

1. Build the normalizer column (M).
2. Build the Dup_Count column (N).
3. Filter to rows where Dup_Count > 1.
4. For each duplicate set, highlight the source-of-truth row green and the duplicate row red.

Hint

Source of truth is the row with the most non-blank fields. Use COUNTA to count fields per row. Use Conditional Formatting with a custom formula to apply the green and red fills.

You pass when:

Your Dup_Count formula reads:

=COUNTIF($M$2:$M$200, LOWER(TRIM(M2))) > 1

And the cell shows:

• 14 duplicate pairs flagged.
• 7 source-of-truth rows in green.
• 7 duplicate rows in red.