Day 15 · Tuesday, 18 August 2026
From the archive
Intermediate
Work out when a warranty runs out
The expiry date isn't stored anywhere — you build it from a purchase date and a length in months.
Task:
You run the returns desk at a hardware store. A customer wants to know if their drill is still under warranty, but the file only has the purchase date and how many months of cover it came with — nobody stores the expiry date itself. Work out the expiry date for each item in column D.
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