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Name a Color

Try this trick; it will help you predict someone's choice of a number between 5 and 10.

First, write the number 7 on a piece of paper and hide it somewhere.

Then, ask someone to respond quickly to these questions:

  • Five times five?
  • Six times six?
  • Name a color?
  • Pick a number between 5 and 10?
Then, in dramatic fashion, reveal your hidden number 7. In "most" instances, people will also pick the number 7.

Did it work? Try the trick multiple times (with new victims). Keep track of how often the number 7 is picked.

Now, the odds of picking a chosen number between 5 and 10 is 1/6 = 17%...but, with this "trick"...!

Why does the trick work? Given the range 5-10, do victims tend to pick interior numbers, namely 6, 7, 8, 9? Do the first two questions set a pattern and prompt the victim to choose the number 7? And, what is the role of the thrid question?

To test these ideas out, repeat the experiment, but shift the questions:

  • Six times six?
  • Seven times seven?
  • Name a color?
And...your results are?