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Back to the Planet of Vuvv

Age 11 to 14
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On the planet Vuvv there are two sorts of creatures. The Zios have $3$ legs and the Zepts have $7$ legs.

 

Image of Zios and Zepts drawn by Thomad Murray

So naturally there are two forms of counting on Vuvv - Zios count in base $3$ and Zepts count in base $7$.

When observed, the creatures on this planet lie on the ground with their legs in the air, so that legs, not bodies, can be most easily counted.

One day four of these creatures, two Zios and two Zepts, sat on the summit of a hill to count the legs of the creatures they could see. One looked to the East, one to the West, one to the South and one to the North.

The creature looking to the West wrote down its number: $122$

The creature looking to the East wrote down its number: $22$

The creature looking to the South wrote down its number: $101$

The creature looking to the North wrote down its number: $41$

In which direction are the two Zios looking and in which directions are the two Zepts looking?

Remember that the creatures must be seeing numbers which could be a combination of Zios' and Zepts' legs.
 

 

 

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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.

NRICH is part of the family of activities in the Millennium Mathematics Project.

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