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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.

digit primes (these are not that many options!) and produce
all possible products.  Then focus on the next clue, etc.

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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