Plan from the supplied facts
Fictional plan explicitly checks every combination of two interfaces, three roles and four record scenarios. Each combination is budgeted at 0.5 hour, with no shared setup in this estimate. This is a full Cartesian plan; whether fewer checks suffice needs a different coverage decision.
| Interface | Roles | Scenarios per role | Combinations / hours |
|---|---|---|---|
| I1 | 3 | 4 | 12 / 6 |
| I2 | 3 | 4 | 12 / 6 |
| Total | 2 interfaces | 3 × 4 each | 24 / 12 |
Work through the choice
Adding 2+3+4 counts labels, not work combinations. The effort basis is the crossed tuple, so 2×3×4=24.
A fourth role is included on both interfaces. What is the new estimate?
Show the worked answer
2×4×4=32 combinations; 32×0.5=16 hours. The addition is eight combinations and four hours.
Material to use in your plan
Use a grid of interface × role × scenario, with one check unit per included tuple. Keep excluded tuples explicit; do not reduce the count merely by adding the dimension labels.