Answers to MEM Challenge 2003

1. It takes four goes to complete the trick.

2. 2401 spoons of barley a day, saving 117649 rolls in a week. They must have had big mice in ancient Egypt!

3. 100 lambs, or 72 chickens, 7 cows and 21 lambs.

4. 360º is the easy answer; but by turning once clockwise and six times anti-clockwise she could turn by 72º; and if she turns twice clockwise and five times anticlockwise, she could turn by 120º. Finally, she could turn by any multiples of these answers such as 144º and 240º. If any of you are ballet dancers, perhaps you could let us know what the world record is for the greatest angle of a single spin!

5. Seven moves are needed  The trick is not to aim for a pile of white plates and a separate pile of blue plates, but to make sure the last move combines two piles into one with blue and white separated. If the plates are on the left to start with, here is one possible solution;

Move 7 plates from left to right (7 L to R); then 6 R to L, 5 L to R, 4 R to L, 3 L to R,
2 R to L, 3 R to L.

6. b) 2     6
      - + - = -
      7   7   7

   c) 1   1   2
      - + - = -
      2   6   3

   d) 3   1    4
      - + -- = -
      4   20   5

   e) 1   2    3     2   4    6
      - + -- = -- ,  - + -- = -- , etc.
      5   20   10    5   20   10

7. Her system fails on 24th June 2004.

Please email me at P.M.Strickland@livjm.ac.uk with any comments or questions. I hope you had fun with Challenge!

Paul Strickland.