If the letters of the word Mississippi are placed in a hat, what is the probability that the first two letters drawn are both "i" if the first letter drawn is not replaced?

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Answer 1 · 2015-10-22T11:37:51

#6/55#

There are #11# (non-unique) letters in "Mississippi"
of which #4# are #i#

A: picking a letter "i" from the letters: "iiiiMsssspp"
P(A) #= 4/11#

B|A: picking a letter "i" from the letters: "iiiMsssspp"
P(B|A) #= 3/10#

#P(A&B) = P(A)*P(B|A) = 4/11*3/10 = 12/110 = 6/55#