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Subj:.....Math Limericks (S674)
          From: MathNexus.wwu.edu
          on 12/11/2009
Drawing from Limerick-Poems.com...

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Source: http://mathnexus.wwu.edu/Archive/problem/detail.asp?ID=182

Limerick Problem #1:
 
 Three different one-digit primes
produce me, if you're using times;
     If my digits you add,
   Another prime will be had.
 Two answers--and nothing else rhymes.

Limerick Problem #2:
 
      There once was a cube 'twas found
Whose two digits, when switched clear around,
         Was the product (quite fair)
            Of a cube and a square,
   And its name will most surely astound.

Source: John Gregory and Dale Seymour's Limerick Number Puzzles (Creative Publications, 1978)
 

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Drawing from tom on 8/21/2009
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 Hint: Take one clue at a time in the order given...try
       to write down what options remain at each step.
 
 

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Finger pointing down
from darrell94590 on 1/2/2006
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Drawing from Ripleys-Believe It Or No
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              THE SOLUTION
 

Solution Commentary: Algebra is not needed to solve
these limericks.  Rather the key is to think your way to a
solution using problem solving skills such as establishing
special cases, looking for patterns, building tables, etc. 

For example, in Limerick #1, start with the set of one-
digit primes (these are not that many options!) and produce
all possible products.  Then focus on the next clue, etc.

For each, ask if the answer unique?

Finally, I wish this resource book was still in print.  My
students always enjoyed these limericks and learned alot
about the reasoning process as a precursor to the formal
proof process.... plus they got a good review of common
mathematical concepts and words.  I will try to include
more limericks later on.
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Drawing from tom on 8/21/2009
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My Solutions:

Limerick Problem #1:

The one-digit primes are 2, 3, 5, and 7.  There are four ways
to multiply three of these numbers.
     2 x 3 x 5 = 30  and 3 + 0 = 3 which is a prime.
     2 x 3 x 7 = 42  but 4 + 2 = 6 which is not a prime.
     2 x 5 x 7 = 70  and 7 + 0 = 7 which is a prime.
     3 x 5 x 7 = 105 but 1 + 0 + 5 = 6 which is not a prime.
The two answers for the limerick are 30 and 70.
 

Limerick Problem #2:

The two digits cubic numbers are 27 and 64.
     27 switched around is 72 which equals 8 x 9, a cube and a square.
     64 switched around is 46 which equals 2 x 23 or 1 x 46.
     Both don't work.
The cube the limerick seeks is 27.

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