EX-21 · Cost model for a real client shape

Difficulty: 🟡 · label difficulty: 2 Stuck? Ask in the clinic thread for EX-21 — one long-running thread per exercise, so the answers accumulate where the next person will look. Submit: post it in Show and Tell titled [solution · EX-21] ..., with your numbers and your interval.

Notebook 07 · ~1 h · Skill: interview Q5

Take a real (or realistic) traffic profile and produce the blended cost, the levers in order, and the residual after the free ones. Then write the paragraph you would say to Finance, including what you refuse to trade.

---