Repeated Appereance
wuyingddg C_K_Yang czp001 liuguangxi a_forsteri abcd faust gerrob zilet hallvabo sinan hervas benito255 lesnik7 R2D2 Caesum Buri dloser nielkh
Public  08/01/13  12xp  Probability  68.8% 
by sinan
How many times must a die with 6 faces be thrown, on average, until one face appears 4 times?
For example, one set of throws might be 1,2,1,4,3,5,2,4,6,1,3,1.
Submit your answer as a/b, where a and b are two relatively prime, positive integers.
How many times must a die with 6 faces be thrown, on average, until one face appears 4 times?
For example, one set of throws might be 1,2,1,4,3,5,2,4,6,1,3,1.
Submit your answer as a/b, where a and b are two relatively prime, positive integers.
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