From the archive

Day 15

Tuesday, 18 August 2026

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.

The daily challenge is part of Pro

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