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  • Early Years Foundation Stage

Always the Same

Age 11 to 14
Challenge Level Yellow starYellow starYellow star
  • Problem
  • Student Solutions

Arrange the numbers 1 to 16 into a 4 by 4 array.

Choose a number and circle it. Cross out the numbers which are in the same row and column as your chosen number.

Repeat this process twice more choosing from the remaining numbers.

This should leave you with one number remaining, circle this one also.

Add up your four circled numbers.

Why do they always add up to 34 whatever way you choose your numbers?


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Fibs

The well known Fibonacci sequence is 1 ,1, 2, 3, 5, 8, 13, 21.... How many Fibonacci sequences can you find containing the number 196 as one of the terms?

Hallway Borders

What are the possible dimensions of a rectangular hallway if the number of tiles around the perimeter is exactly half the total number of tiles?

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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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