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Proving a witch weighs the same as a duck (Posted on 2005-02-21) Difficulty: 2 of 5
Suppose the witch weighs W pounds, and the duck weighs D pounds. Also, suppose their average weight is A pounds. (Their combined weight is 2A)

W + D = 2A. (Given)
W = 2A - D. (Subtract D)
W - 2A = -D (Subtract 2A)
W(W - 2A) = W(-D) (Multiply by W)
W(W - 2A) = (2A - D)(-D) (Substitute 2A-D for W using the given equation)
W - 2AW = -2AD + D (Distribute)
W - 2AW + A = D - 2AD + A (Add A)
(W-A)(W-A)=(D-A)(D-A). (Factor)
(W-A) = (D-A)². (An expression times itself equals the expression squared)
(W-A) = (D-A) (Square root)
W = D (Add A)

In other words, a witch weighs the same as a duck.

Where did I go wrong?

See The Solution Submitted by Dustin    
Rating: 3.0000 (4 votes)

Comments: ( Back to comment list | You must be logged in to post comments.)
re: Monty Python logical method | Comment 8 of 12 |
(In reply to Monty Python logical method by Larry)

Very Good Larry,

You missed one minor detail though.  It happens to be one of my favorites.  When the camera first cuts to Sir Bedevere, he is conducting an experiment to see if a swallow can cary a coconut.  The poor bird fails, disproving Author's supposed theory.

Another favorite of mine is the line.  "A moose once bit my sister." 

Did you catch that one?

  Posted by Bruce Brantley on 2005-02-22 18:02:45
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