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Exploring Wild & Wonderful Number Patterns

EWWNP means Exploring Wild and Wonderful Number Patterns Created by Yourself! Investigate what happens if we create number patterns using some simple rules.

Sending Cards

This challenge asks you to investigate the total number of cards that would be sent if four children send one to all three others. How many would be sent if there were five children? Six?

Dice and Spinner Numbers

If you had any number of ordinary dice, what are the possible ways of making their totals 6? What would the product of the dice be each time?

Sam's Quick Sum

Age 7 to 11
Challenge Level

Congratulations to Jamie, St Angela's School, Forest Gate, London; Joshua, Amptill, Bedfordshire; Sohail, Predesh, Gurpreet, Jessica and James, Jack Hunt School, Peterborough; Charlotte, Helen, Bella, Charis, Christianne, Peach, Sheila, Cheryl, Pen and Lyndsey, Laura and Emma, The Mount School, York. Here is Jamie's solution:

There are $900$ numbers between $100$ and $999$ so you can halve the number $900$ to see how many pairs you get.
Each pair adds up to $1099$ because if you add $100$ to $999$ the answer is $1099$ and if you add $101$ to $998$, or $102$ to $997$ and so on you get the same answer.
The sum of all the three-digit numbers is $450 \times 1099 = 494550$.

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.
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