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History of Morse

This short article gives an outline of the origins of Morse code and its inventor and how the frequency of letters is reflected in the code they were given.

Very Old Man

Is the age of this very old man statistically believable?

Data Matching

Use your skill and judgement to match the sets of random data.

Discussing Risk and Reward

Age 16 to 18
Challenge Level

Use a mixture of common sense and mathematics. 
Don't forget that risk is a personal preference -- you cannot be 'wrong' if you choose to accept a certain level of risk in an activity (although you might be foolish; but that's a different matter!)