# Chapter 10 — Practice-on-your-own hints — Companion > Diagnostic hints for the Practice-on-your-own problems from Chapter 10 of The Defensible Decision. Canonical URL: https://www.thedefensibledecision.com/ch/10/practice/ [← Chapter 10 companion](/ch/10/) · [All chapter resources](/ch/) Short diagnostic hints for the two Practice on your own problems in this chapter. Attempt each problem before opening the hint. Complete answers appear in Appendix G of The Defensible Decision: Practice Workbook. ### Problem 1 — the confidently-wrong Smart Narrative Restated: A Smart Narrative paragraph on a Q3 sales page reads «Overall performance was strong, with growth across all regions and consistent improvement in customer satisfaction.» The underlying charts show that EMEA missed plan by 12% and satisfaction dropped 3 points in APAC. Name why this failure mode is the highest-risk of the four AI visuals and the specific edit or removal you would make. Show a diagnostic hint Diagnostic cue. Treat a fluent narrative as a claim to verify against the BRD and source, not as an explanation to accept. Complete answers appear in Appendix G of The Defensible Decision: Practice Workbook. ### Problem 2 — the Decomposition Tree that no one else can reproduce Restated: A colleague quotes to leadership: «The Decomposition Tree shows plant 0477’s advanced-surgical line is the highest backorder driver.» When leadership tries the same report on Monday, the tree picks EMEA region and plant 0631. Name why the two people saw different paths, and the one-sentence verification move that would have caught the filter dependence before the Friday quote. Show a diagnostic hint Diagnostic cue. Check whether another analyst can reproduce the visual's path, filters, and interpretation. Complete answers appear in Appendix G of The Defensible Decision: Practice Workbook. ### Related on this site - [Chapter 10 companion page](/ch/10/) — further reading, self-check quiz, and the four AI-visuals triage activity. - [All chapter companion pages](/ch/). - [Feedback](/errata/) — share corrections and improvement opportunities across all chapters. ### About the three-tier Practice format Each chapter of the book closes with a three-tier Practice block adapted from Cole Nussbaumer Knaflic's course-adoption pattern in Storytelling with Data: Let's Practice!: Practice with us (one worked problem with full solution in the book), Practice on your own (open problems with complete answers in Appendix G of the Practice Workbook; this page offers short diagnostic hints), and Practice at work (an open-ended prompt to apply the chapter's move to a live artifact). This page hosts the middle tier.