Psychic Math

Copyright ©2003 by Paul Niquette.  All rights reserved.

1. Pick the number of times 
a week that you would like 
to have dinner out.
Let p be the number you pick.
Notice, if you have only one
"dinner" per day, p < 8.
2. Multiply this number by 2. 2p
3. Add 5. 2p + 5
4. Multiply by 50.  50(2p + 5) = 100p + 250
5. If you have already had your 
birthday this year, add 1753. 
If you have not, add 1752.
100p + either...
    250 + 1753 = 2003 or...
    250 + 1752 = 2002
6. Now subtract the four digit 
year in which you were born.
100p + either...
    2003 - y or 2002 - y

ophisticated solvers of this puzzle as well as psychics know that the difference between the year of your most recent birthday and that in which you were born is your age.  Of course, using the procedure in the statement of this puzzle, you did come out younger than you really are -- unless you happened to notice that the puzzle was published in 2003.

To make the puzzle work for your e-mail recipients in the future, you will need to change the addends in Step 5 to 250 and 251 years ago.  Then, too, your recipients better not be more than five-score years old, for we see only two digits of age allowed by the prescribed Psychic Math set forth above.

How might you change the procedure to accommodate centenarians who enjoy solving puzzles?
There doubtless exists a conventional name for this huge class of prestidigitation, in which...
  • numerical information is acquired from the subject -- "Pick the number of [whatever]"...
  • accompanied by extraneous comments -- Multiply by [some number] "just to be bold"
  • manipulated with circuitous arithmetic -- ..."add or subtract" [some strange-looking number].
...disclosing an astounding insight if not a predestined miracle.  If you know what that name is, please fix it firmly in your mind and concentrate.  Better still, write to and send along your favorite [whatever-you-call-it].

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