Re: A Trivial Arithmetic Problem

Carl Ginnow:

Hints : The starting number is 13.  After each operation, the result is
a whole number. Use this fact to check answers at each "Divide by"
operation.
 
Start with an unlucky number for a Friday.

13.

Multiply by the gables on Hawthorn's house.

*7 = 91.

Add the number a stitch in time saves.

+9 = 100.

Add the number of blind mice.

+3 = 103.

Subtract the number of William Pène du Bois' balloons.

(First google.)
-21 = 82.

Add the number of wonders of the world.

+7 = 73.

Subtract the number of miles in Camptown's racetrack.

+5 = 68.

Subtract the number of strings on a violin.

-4 = 64.

Divide by the number of vertices on a regular hexahedron.

/8 = 8.

Add the number of the engine that ran on Chicago line.

(Second google.)
One source says 9, another 999.

+ that = 17 or 1007.

Multiply by the number of gentlemen of Verona.

*2 = 34 or 2014.

Add the atomic number of the element whose symbol is the 25th letter of
the alphabet.

(I thought I knew it, but I did a third google to make sure.)
+39 = 73 or 2053.

Divide by the number of hills of Rome.

/7 = not an integer in either case.  I give up.
--
Mark Brader    |        this                                take
Toronto        |    "If      is          shall       really      to
msb@vex.net    |                flying I       never                it."
               |             -- Piglet ("Winnie-the-Pooh", A.A. Milne)

My text in this article is in the public domain.