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Zin Obelisk

Age 11 to 14
Challenge Level

In the ancient city of Atlantis a monument called a Zin Obelisk was built in honour of the goddess Tina.

The structure (a cuboid) took less than two weeks to complete.

Your task is to determine on which day of the week the monument was completed.

You will need a set of information cards to solve the problem.

For the set, you'll need to print off this Word document or this pdf.

Printable NRICH Roadshow resource. 

Sample zin cards


The original version of this problem appeared in "Improving Work Groups: A Practical Manual for Team Building" by Dave Francis & Don Young.

The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice.
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