ap0258

First, guessing on 50% even if you eliminated 1 choice will not garantee you getting half them right

as you should know, it is a distribution, an easy one I belive, it will be symetrical and you have a 50% right would be in the center or the distribution, 0 on one end and 100 on the other end

P(0) = 0
P(1) = 0
P(2) = 0
P(3) = 0
P(4) = 0
P(5) = 0
P(6) = 0
P(7) = 0
P(8) = 0
P(9) = 0
P(10) = 0
P(11) = 0
P(12) = 0
P(13) = 0
P(14) = 0
P(15) = 0
P(16) = 1.0617e-12
P(17) = 5.246e-12
P(18) = 2.419e-11
P(19) = 1.044e-10
P(20) = 4.2282e-10
P(21) = 1.6107e-9
P(22) = 5.784e-9
P(23) = 1.9615e-8
P(24) = 6.2932e-8
P(25) = 1.9131e-7
P(26) = 5.5187e-7
P(27) = 0.0000015125
P(28) = 0.0000039434
P(29) = 0.0000097904
P(30) = 0.000023171
P(31) = 0.000052321
P(32) = 0.00011282
P(33) = 0.00023247
P(34) = 0.00045811
P(35) = 0.00086386
P(36) = 0.0015597
P(37) = 0.0026979
P(38) = 0.0044729
P(39) = 0.0071107
P(40) = 0.010844
P(41) = 0.015869
P(42) = 0.022292
P(43) = 0.030069
P(44) = 0.038953
P(45) = 0.048474
P(46) = 0.057958
P(47) = 0.06659
P(48) = 0.073527
P(49) = 0.078029
P(50) = 0.079589
P(51) = 0.078029
P(52) = 0.073527
P(53) = 0.06659
P(54) = 0.057958
P(55) = 0.048474
P(56) = 0.038953
P(57) = 0.030069
P(58) = 0.022292
P(59) = 0.015869
P(60) = 0.010844
P(61) = 0.0071107
P(62) = 0.0044729
P(63) = 0.0026979
P(64) = 0.0015597
P(65) = 0.00086386
P(66) = 0.00045811
P(67) = 0.00023247
P(68) = 0.00011282
P(69) = 0.000052321
P(70) = 0.000023171
P(71) = 0.0000097904
P(72) = 0.0000039434
P(73) = 0.0000015125
P(74) = 5.5187e-7
P(75) = 1.9131e-7
P(76) = 6.2932e-8
P(77) = 1.9615e-8
P(78) = 5.784e-9
P(79) = 1.6107e-9
P(80) = 4.2282e-10
P(81) = 1.044e-10
P(82) = 2.419e-11
P(83) = 5.246e-12
P(84) = 1.0617e-12
P(85) = 0
P(86) = 0
P(87) = 0
P(88) = 0
P(89) = 0
P(90) = 0
P(91) = 0
P(92) = 0
P(93) = 0
P(94) = 0
P(95) = 0
P(96) = 0
P(97) = 0
P(98) = 0
P(99) = 0
P(100) = 0


using the numbers above you can calculate the probabilty of you getting x many correct out of a 100 you guessed on randomly after eliminating 1 choice

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regarding the chosing the same answer for each time you random guess

if the answers are randomly set by the CFAI, and they probably use some random program to switch the options around, so that C on your paper is not the C on my paper

in that case, guessing randomly or selecting the same answer would give you the same result if it is on a test of 1000000 questions and assuming you are a true random number generator (which you cant be, cause nothing is, and esp you cause you will be biased)

if you start getting biased towards one of them, and they are truly random, you would be hurting your chances, so best stick to one of them

again all this is theoretical statistics stuff that would apply under large numbers, in a test of a 120 questions, even if the CFAI is using a random order of questions, they may not end up being so random

lool off to bed, i hope something in here made sense