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  • Early Years Foundation Stage

Symmetrical Semaphore

Age 7 to 11
Challenge Level Yellow star
  • Problem
  • Getting Started
  • Student Solutions

You answered this problem very well. Toby and Jodi from King's Park Primary School sent us the following:

First of all we decided which letters were symmetrical (D, R, U and N) and wrote these down. We then used these letters to make a word which we thought would be used in a semaphore message - RUN! We also made up the word - nun.

Some of you didn't pick up on the letter D being symmetrical. Remember, a person standing behind would still see just one flag up in the air. Rachael from Ardingly College, and Chris and Joseph from Moorfield Junior School, also found the word "urn" which, as Chris and Joseph pointed out, is an ancient Greek pot.

So that's three words in total. If you find any others, do email us.

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Eight Dominoes

Using the 8 dominoes make a square where each of the columns and rows adds up to 8

Prime Magic

Place the numbers 1, 2, 3,..., 9 one on each square of a 3 by 3 grid so that all the rows and columns add up to a prime number. How many different solutions can you find?

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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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