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These two group activities use mathematical reasoning - one is numerical, one geometric.

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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.

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Place this "worm" on the 100 square and find the total of the four squares it covers. Keeping its head in the same place, what other totals can you make?

Reverse Trick

Stage: 2 Challenge Level: Challenge Level:1

Solution 1
From Jonathan at St. Andrew's Primary School, Cullompton:

My answer is 272727.
This is how I worked it out. If you take the first example and set it out like this: (9+) 12 = 21 I worked out that 21 - 12 = 9 and the same with 51 - 15 = 36 (second example).
Therefore 414141 - 141414 has to equal the secret number, which is 272727.

Solution 2
From Hang Hao who goes to Pei Hwa Presbyterian Primary School, Singapore:

The answer to this problem is 272727.
Reversing 141414 gives 414141.
The secret number add 141414 gives 414141.
Therefore the secret number is obtained by 414141-141414 = 272727.