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A Magical Trick to De-cypher Then Mimic

Take your house number.

Double it.

Add five.

Multiply by half a hundred.

Add your age (if you are under 100).

Add the number of days in a year.

Subtract 615.

What do you see......

Why does this "trick" work?
Can you explain the role of each line? Why can't you be over age 100?
If you added the number of weeks in a year other than the number of days, how would the number 615 change?

Make up a trick like this yourself....try your magic on others!

And J.S. (Meridian) did just that, as he wrote:

I was looking at the puzzle this week, "A Magical Trick to De-Cypher ... ", and I thought about presenting this sort of thing:

  • Reverse the order of steps five and six... does the trick still work? Why?
  • Can you find another reversible pair? Why does it work?
  • What happens if you reverse the order of steps four and seven? Why?
  • What happens if you move step four to a position immediately before step seven? Why?
Thanks, J.S.....!


Source: Morris Mandel, The Jewish Press

Hint: Assume your house number was N and your age was A...now work slowly through the trick.


Solution Commentary: Simplify: