The Overdue Interlibrary Loan
A regional library service runs a courier loop linking four branches. A book requested by a student sits at Northgate and must reach Southbank within five working days. The courier visits Northgate only on Mondays and Thursdays, and Southbank only on Tuesdays and Fridays. The student's deadline falls on a Friday. The catalogue record shows the book as 'available' at Northgate, but a handwritten note on the hold slip reads 'possibly on display shelf, check'. The librarian has three options: (a) send the book on the next courier run and hope it arrives in time, (b) telephone Northgate to confirm the book is physically on the shelf before dispatch, or (c) ask the student to collect it from Northgate, a 90-minute round trip. The student has already stated they cannot travel.
1. Which option should the librarian choose, and why?
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Option (b). The record says 'available' but the handwritten note introduces doubt, and the courier schedule is tight: if the book is not actually on the shelf, a Monday dispatch could still miss the Friday deadline. A phone confirmation costs minutes and removes the uncertainty. Option (a) gambles on incomplete information; option (c) is ruled out because the student has said they cannot travel. The judgement being tested is recognising when a small verification step protects a deadline that the schedule barely allows.
2. Suppose Northgate confirms the book is on the shelf on a Wednesday. Trace the earliest arrival at Southbank.
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Northgate is served Monday and Thursday, so the earliest dispatch is Thursday. Southbank is served Tuesday and Friday, so the book reaches Southbank on Friday. That is exactly the deadline day, with no margin. The reasoning shows the schedule leaves zero slack, which reinforces why confirming availability first was essential - any delay at Northgate would push arrival past the deadline.