Page 0065

(1) Making a slam with three finesses:

If you assume that each finesse is 50-50, like tossing

a coin, then there 8 (2 x 2 x 2) possible outcomes.

(2 x 2 x 2 is 2 to the power of 3 - I knew there would

be a 3 in there somewhere!) Using the coin-tossing

analogy, the eight possible outcomes are HHH,

HHT, HTH, THH, HTT, THT, TTH, TTT. For the

first four, two or three finesses are successful; for the

last four, two or three finesses fail, so the answer is

indeed 50-50.

(2) Arrow-switching:

Sorry, I looked, but there is no simple explanation

of why the answer is one-eighth. A very detailed but

not-so-simple explanation can be found at

www.ebu.co.uk/documents/media/bridge-move

ments-the-maths.pdf.

The simplest I could find is by David Stevenson

and is at www.blakjak.org/lwz_ste3.htm

I can do no better than quote David's last

sentence: 'Arrow-switching is fair, and roughly one

board in eight should be switched; trust me!'

(3) Sharing the same birthday:

If you have two people, the chance that they will not

have the same birthday is 364/365. If you add in a

third person, then the chance that all three have

different birthdays is 364/365 multiplied by 363/365

(that is about .99). Then multiply that result by

362/365 and so on. When you include the 22nd

person (multiplying the previous answer by

344/365) you get .52. It is the 23rd person who tips

the balance to .49. If the chance that 23 people will

not have the same birthday is less than half, then the

chance that two of the 23 will have the same

birthday is greater than 50%.

The next time you are at a gathering with thirty or

more people, you could try it out. Have a little side

bet, if you can; the odds of a shared birthday among

thirty people is just over 70%.

65

August 2015 English Bridge

www.ebu.co.uk

(4) Continuous scoring names:

You can while away many an hour looking up the

dates from the 16-board scoring table. If you

wanted the results to have an international flavour,

you could call 1460 a Basle (the founding of the

university) and 1703 a Rultusk (Sweden beat Russia

in the battle of). An American version would have

to start late (nothing before 1492) but could include

a Morse (1844: Samuel Morse sends the first

telegram), an Einstein (1916: Albert Einstein

presents the Theory of Relativity) and an Apollo

(1969: first moon landing).

A well-rounded English list would include a mix

of the military, the arts, science and sport: a Stirling

(1304: Stirling Castle falls to Edward I), a Shakes peare

(1609: his sonnets are first published), a

Handel (1717: Water Music first performed in

London), a Quebec (1759: Quebec captured from

the French), a Darwin (1833: HMS Beagle arrives in

Port Deseado, Patagonia), a Wimbledon (1877: first

tennis championships) and a Sherlock Holmes (1887:

publication of Conan Doyle's first Holmes story, A

Study in Scarlet).

(5) Player numbers:

The bridge magazines of the time contain lots of

useful information, but building the lists wasn't

always as simple as that. Sometimes teams were

selected and then changed; in 1939 a name was

changed but the team was the same! (Molly Withers

got married between her selection and the

competition itself, changing her last name to Furse,

and acquiring her husbands' initials.)

My thanks to Peter Hasenson, Richard Fleet, Wolf

Klewe and Jeremy Dhondy for their assistance in the

production of the lists.

continued on next page

Online ExtraOnline Extra

Bridge Numbers Appendix - by Simon Cochemé

A Useful Appendix to Simon Cochemé's article on pages 13-14)

Index

  1. Page 0001
  2. Page 0002
  3. Page 0003
  4. Page 0004
  5. Page 0005
  6. Page 0006
  7. Page 0007
  8. Page 0008
  9. Page 0009
  10. Page 0010
  11. Page 0011
  12. Page 0012
  13. Page 0013
  14. Page 0014
  15. Page 0015
  16. Page 0016
  17. Page 0017
  18. Page 0018
  19. Page 0019
  20. Page 0020
  21. Page 0021
  22. Page 0022
  23. Page 0023
  24. Page 0024
  25. Page 0025
  26. Page 0026
  27. Page 0027
  28. Page 0028
  29. Page 0029
  30. Page 0030
  31. Page 0031
  32. Page 0032
  33. Page 0033
  34. Page 0034
  35. Page 0035
  36. Page 0036
  37. Page 0037
  38. Page 0038
  39. Page 0039
  40. Page 0040
  41. Page 0041
  42. Page 0042
  43. Page 0043
  44. Page 0044
  45. Page 0045
  46. Page 0046
  47. Page 0047
  48. Page 0048
  49. Page 0049
  50. Page 0050
  51. Page 0051
  52. Page 0052
  53. Page 0053
  54. Page 0054
  55. Page 0055
  56. Page 0056
  57. Page 0057
  58. Page 0058
  59. Page 0059
  60. Page 0060
  61. Page 0061
  62. Page 0062
  63. Page 0063
  64. Page 0064
  65. Page 0065
  66. Page 0066
  67. Page 0067
  68. Page 0068
  69. Page 0069
  70. Page 0070
  71. Page 0071
  72. Page 0072
  73. Page 0073
  74. Page 0074