Reconstructing a Morning Visitors' Register
An entry register from the visitors' lobby of a district office is being audited after a complaint that badges were issued without checking identity. The register for one morning records five visitors - Rawat, Menon, Dsouza, Bano and Iyer - who arrived one each at 10:00, 10:30, 11:00, 11:30 and 12:00, and were given badges in five colours: blue, red, green, yellow and white. They went to five sections: Estt, Ops, Tech, Vig and Admn. The clerk's marginal notes, which are the only surviving record, say: (i) Rawat came at 11:00 and was given the blue badge; (ii) the green badge was issued at 10:00; (iii) Menon arrived immediately before the visitor who took the yellow badge; (iv) the visitor to Tech arrived at 12:00; (v) Dsouza arrived immediately after the visitor who took the red badge; (vi) Bano went to Ops and arrived before Iyer; (vii) the visitor to Admn arrived at 10:30; (viii) Iyer took the white badge; (ix) the visitor to Vig arrived before the visitor to Estt.
1. Reconstruct the full register - time, visitor, badge colour and section for each of the five - showing the deduction that fixes the red badge.
Read the worked answer
Fixed points: 11:00 = Rawat, blue. 10:00 = green. 10:30 = Admn. 12:00 = Tech.
Where can the red badge be? Not 10:00 (green) or 11:00 (blue). Not 10:30, because Dsouza arrives immediately after red and 11:00 is already Rawat. Not 12:00, as there is no later slot. So red = 11:30 and Dsouza = 12:00.
Yellow and white occupy 10:30 and 12:00. If yellow were at 10:30, Menon would be at 10:00 and white would fall at 12:00 - but 12:00 is Dsouza, and Iyer holds white. Contradiction. So yellow = 12:00, Menon = 11:30, white = 10:30 = Iyer (Admn). The remaining person at 10:00 is Bano (Ops, green), consistent with Bano arriving before Iyer. Sections left for 11:00 and 11:30 are Vig and Estt; Vig first gives Rawat = Vig, Menon = Estt.
| Time | Visitor | Badge | Section |
|---|---|---|---|
| 10:00 | Bano | Green | Ops |
| 10:30 | Iyer | White | Admn |
| 11:00 | Rawat | Blue | Vig |
| 11:30 | Menon | Red | Estt |
| 12:00 | Dsouza | Yellow | Tech |
2. The clerk proposes two corrections: (1) move Iyer to 12:00 'so the badge colours read in order'; (2) strike out the Menon line because Menon's signature is missing. Assess each proposal against the constraints.
Read the worked answer
(1) Moving Iyer to 12:00 breaks at least three constraints at once. Iyer carries white, so white would sit at 12:00; yellow would then have to be at 10:30, which forces Menon to 10:00 - but 10:00 is green, and Menon's 10:00 entry would also displace Bano, who must arrive before Iyer and go to Ops. The proposal is a preference for pattern, not evidence.
(2) Deleting the Menon line is also wrong, though the defect is real. Missing signature is a flaw in the record, not proof that the visit did not occur; removing the line destroys the only evidence that Menon was at Estt at 11:30 and silently un-fixes the red-badge deduction.
Correct handling: leave every original line intact, add a marginal note with date, initials and reason - 'signature not obtained, sentry to be questioned' - and attach the clerk's proposed changes as a separate, rejected note. A register is corrected by annotation, never by rewriting to fit a theory.
3. Name the single additional check you would order first, and say exactly what it would prove or disprove.
Read the worked answer
Order the Tech section's appointment diary or visitor slip for that morning. It is the one independent record that can pin a named visitor to a specific clock time.
Why this one: the whole reconstruction rests on Tech being at 12:00 and Admn at 10:30. If the Tech diary shows Dsouza's meeting at 12:00, the table stands and the audit moves on to why identity was not checked. If it shows the Tech visitor at 10:30, then the Admn and Tech clues collide, the reconstruction collapses, and the register must be treated as unreliable as a whole rather than being patched.
Secondary checks - the badge issue counterfoils for white and green, and lobby camera timestamps - come after this, because they confirm people, whereas the diary confirms the time structure everything else hangs on.