Letters (probability)
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LSB
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the attachments in this post are quite large. I am reattaching as word documents.
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- Letters.doc
- letters
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parallel_chase
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The probability of A letter going to A envelop and B, C, and D in wrong
A going into right envelop is 1/4
B going into wrong envelop is 2/3 ( 1-1/3)
C going into wrong envelop is 1/2
D automatically will go into the wrong envelop 1
1/4*2/3*1/2*1 = 1/12 (multiplication because everything occurs at once)
Similarly the same procedure will follow for B, C & D and the result will also be the same
1/12+1/12+1/12+1/12 = 4/12 = 1/3.
A going into right envelop is 1/4
B going into wrong envelop is 2/3 ( 1-1/3)
C going into wrong envelop is 1/2
D automatically will go into the wrong envelop 1
1/4*2/3*1/2*1 = 1/12 (multiplication because everything occurs at once)
Similarly the same procedure will follow for B, C & D and the result will also be the same
1/12+1/12+1/12+1/12 = 4/12 = 1/3.
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4meonly
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Anybody, please find the flaw in my reasosning:
1. To make 1st letter with correct adress:
1/4*2/3*1/2*1 = 1/12
2. To make 2nd letter with correct adress:
3/4*1/3*1/2*1 = 1/8
3. To make 3rd letter with correct adress:
3/4*2/3*1/2*1 = 1/4
4. To make 4th letter with correct adress:
3/4*2/3*1/2*1 = 1/4
summ will be 17/24
1. To make 1st letter with correct adress:
1/4*2/3*1/2*1 = 1/12
2. To make 2nd letter with correct adress:
3/4*1/3*1/2*1 = 1/8
3. To make 3rd letter with correct adress:
3/4*2/3*1/2*1 = 1/4
4. To make 4th letter with correct adress:
3/4*2/3*1/2*1 = 1/4
summ will be 17/24
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canuckclint
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The flaw is in 1 and multiplications in general4meonly wrote:Anybody, please find the flaw in my reasosning:
1. To make 1st letter with correct adress:
1/4*2/3*1/2*1 = 1/12
2. To make 2nd letter with correct adress:
3/4*1/3*1/2*1 = 1/8
3. To make 3rd letter with correct adress:
3/4*2/3*1/2*1 = 1/4
4. To make 4th letter with correct adress:
3/4*2/3*1/2*1 = 1/4
summ will be 17/24
1 should be = 2/24
