Build a time-state record
Synthetic task T-I runs from 09:00 to 15:00. It is worked on 09:00–10:00 and 13:00–15:00, waits for an external input 10:00–12:00, and is deliberately paused by the lead 12:00–13:00. Intervals do not overlap.
| Interval | State | Duration |
|---|---|---|
| 09:00–10:00 | Active effort | 1 hour |
| 10:00–12:00 | Waiting input | 2 hours |
| 12:00–13:00 | Lead pause | 1 hour |
| 13:00–15:00 | Active effort | 2 hours |
Interpret elapsed delay by its cause
- Capture nonoverlapping state intervals
- Total three active hours
- Separate two waiting and one paused
- Review input response before adding staff
An unrecorded interval stays unknown; do not silently call every gap blocked time or productive work.
Six elapsed hours contain three active, two waiting and one paused. Extra staff would not have supplied the absent external input under these facts. Use the state record to choose the relevant follow-up rather than treating six hours as labour.
What fraction of elapsed time was active effort?
Show the worked answer
Half, 3 / 6 = 50%. The remaining half is two waiting hours and one deliberate pause.