After the typist writes 100 letters and addresses 100 envelopes she inserts the letters randomly in to the envelopes(1 letter per envelope). What is the probability that exactly 1 letter is inserted in an improper envelop?
0
1-1/100
1/100!
1/100

• ans is 0. because if 1 letter put wrong,definitely there is another letter get wrong envelop..so probability of exactly 1 letter is inserted in an improper envelop is zero.
  
• 13 years agoHelpfull: Yes(5) No(0)
• the ans is 0,1 letter means the probability is 0
• 13 years agoHelpfull: Yes(4) No(1)
• the probability is 0 because if x's letter goes into y's envelope then y's letter must be in x's envelope. so atleast two letters must be in improper envelopes
• 13 years agoHelpfull: Yes(4) No(0)