Success: test equal-box plans against both arithmetic and constraints. Prepare fictional 36-book scenario. (AC9M5N02, AC9M5N09)
- Frame · 2 min. Read the constraint: six boxes available, capacity eight each. This is an invented problem.
- Model · 4 min. Put six books in each available box:
6×6=36,6≤8, so equal sharing and capacity both work. - Guided options · 5 min. Test four boxes of nine: arithmetic works, but nine exceeds each box's capacity of eight. Test five boxes: 7 each and one left; not equal shares of all 36.
- Independent choice · 7 min. Learners recommend a plan in a table
number of boxes / books each / spare capacity / constraint. They may recommend four boxes of nine only if boxes with capacity at least nine become available, and say why. - Partner audit · 4 min. Partners ask whether the plan fits every stated condition. No prices have been supplied, so no one can calculate cheapest.
- Exit · 3 min. “Why isn't four boxes of nine the immediate plan?” Key: each available box holds at most eight books.