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Log Lattice

Age 16 to 18
Challenge Level Yellow star
  • Problem
  • Getting Started
  • Student Solutions

Thank you to everyone who submitted solutions to this problem.

Jessica form Tiffin Girls school has found a really nice way of organising all the given logarithms into a table.



This table nicely captures all the information we can get about the relative sizes of the logarithms without calculating them, by making use of the fact that $\log_b{a}$ increases in size as you increase $a$ or decrease $b$.

It also makes it much easier to read off all the different ways you could complete the given grid, of which there are quite a few. Here is one way Jessica has given to complete the grid.


You can read Jessica's full solution here .

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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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