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## 'Odd One Out' printed from http://nrich.maths.org/

The interactivity below has been programmed to generate random
numbers according to 6 different and well defined random processes.
You can generate as many of these sets of data as you like by
pressing the 'New Data' button.

HOWEVER: for each process there is a deliberately placed bad item
of data (whose location varies each time you make new numbers)
which breaks the pattern shown by the other numbers.

By searching for structure and
suspicious numbers, can you work out which is the likely odd one
out in each case? (full screen mode)

This text is usually replaced by the Flash movie.

Use the scroll bars to input your choices of the bad rows and
press 'Check' to see if you are correct: if you are then the whole
column will turn red; otherwise the computer will ignore you. Good
luck!

Discuss: Can you ever
be certain
that you are correct in your
assessment of the odd ones out? Can you give a statistical
justification as to why your guesses are likely to be
correct?