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statistics help please!!!!

m n

(edited 13 years ago)

i.am.lost

The probability of getting a result divisible by 3 each roll is 1/3. Let D indicate the result is divisible by 3 {3,6} and N that it is not {1,2,4,5}

Number of rolls with results divisible by 3 = 2
Elementary events = NNDD NDND NDDN DNND DNDN DDNN
PMF (X=2) = (2/3*2/3*1/3*1/3)*6 = 8/27

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The probability of getting a 5 each roll is 1/6. Let F indicate the result is 5 and A that it is anything else {1,2,3,4,6}

Number of rolls with result 5 = 1
Elementary events = AAAF AAFA AFAA FAAA
PMF (Y=1) = (1/6*1/6*1/6*5/6)*4 = 5/324

(edited 13 years ago)