BrainBashers - Brain Teasers and Puzzles

Puzzle 717

Which is larger:

centimetres in a mile miles travelled by light in a second

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Puzzle 718

A Proof That 2 = 1. Let A = B:

           A = B

multiply by A on both sides:

         A x A = A x B

subtract B x B from both sides:

   A x A − B x B = A x B − B x B

factorise:

  (A + B)(A − B) = B(A − B)

divide by (A − B) on both sides:

       (A + B) = B

replace A with B:

         B + B = B

factorise:

          2B = B

divide by B on both sides:

           2 = 1

Where lies the flaw in the logic?

workings answer print

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Puzzle 719

What kind of room has no windows or doors?

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Puzzle 720

Can you place a different 3-letter word into each of the brackets to create two longer words?
finger[---]toe copy[---]walk don[---]hole out[---]trot every[---]dream
In the following example, the word 'book' creates the words 'cookbook' and 'bookcase'.
cook[book]case

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