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Children from Beaumaris North Primary School, Melbourne told us:
In our Year 3 Enrichment group we discussed all the possible sets that could be found. Here is what we found!Olly from North Molton Primary also found:
multiples of $13$: {$13, 39, 91, 143$}Can you find any more? How about triangle numbers and tetrahedral numbers?
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?
You can trace over all of the diagonals of a pentagon without lifting your pencil and without going over any more than once. Can the same thing be done with a hexagon or with a heptagon?