Hi, I thought you may like this Mentalrobics exercise from Braingle.com:
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Patterns

Have you ever remembered a phone number by visualizing the pattern of telephone button pushes or by using a little math (416-2550: 4 squared is 16, 25 doubled is 50)? If so, then you have already used patterns to help you remember a fact.

Looking for patterns in dates, phone numbers, addresses, etc. will give you a much better chance at remembering the information later. This is because you've instantly made the information more meaningful, you've concentrated on it long enough to push it into long-term memory, and you've chunked it [ For more on 'chunked it' go here: http://www.braingle.com/mind/24.html ].

In the above example, you only need to remember "4 squared, 25 doubled" which is, at 4 chunks, much easier to remember than the original 7 chunks.
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For more mind exercises: http://www.braingle.com/mind/