Declare the quantity basis of the tier
Synthetic offer: one carton has six pieces. All pieces cost HKD 10 each below ten pieces, or HKD 8 each at ten or more pieces. The tier counts pieces and applies to the whole line, not just pieces above ten. Two cartons mean twelve pieces. Prices and the tier are invented inputs, with no tax or delivery charge included.
| Constraint | Required record | Example decision rule |
|---|---|---|
| Unit conversion | Carton revision / six pieces | 2 cartons → 12 pieces |
| Tier basis | Piece threshold 10 | Do not compare carton count 2 with 10 |
| Price application | All units on line | 12 × 8 = HKD 96 |
Test the tier boundary and converted quantity
| Case | Input | Expected decision |
|---|---|---|
| 9 pieces | Below 10 | 9 × 10 = HKD 90 |
| 2 cartons | 12 pieces | 12 × 8 = HKD 96 |
- Read ordered unit
- Convert with evidenced pack map
- Select tier in pieces
- Apply price to whole line
An unconfirmed pack size leaves the tier unresolved; do not assume the latest carton conversion applies to every offer.
Exactly ten pieces are ordered. What is the example line amount?
Show the worked answer
HKD 80: ten meets the inclusive tier and all ten use HKD 8.
Add an explicit all-unit versus marginal-pricing field to the requirement; a threshold alone does not define the amount.