If four letters are placed into 4 addressed envelopes at random, the probability that exactly two letters will go wrong is

Ravi writes 5 letters and addresses 5 envelopes. If the letters are placed in the envelopes at random, then the probability that a least one letter goes into the wrong envelope is

Ravi writes 5 letters and addresses 5 envelopes. If the letters are placed in the envelopes at random, then the probability that a least one letter goes into the wrong envelope is

There are four letters and four envelopes, the letters are placed into the envelopes at random, find the probability that all letters are placed in the wrong envelopes.

n different letters are placed in n different addressed envelopes at random. Find the probability that (i) no letter is placed in right envelope i.e., all the letters are placed in wrong envelopes. (ii) atleast one letter is placed in right envelope.

A: There are 4 letters and 4 addressed envelopes. If the letters are put in the random in the envelopes , the probability that all the letters may be placed in wrongly addressed envelopes is 3//8 . R: If n letters are put at random in the n addressed envelopes , the probability that all the letters may be in wrong envelopes = 1- (1)/(1!) +(1)/(2!)-(1)/(3!)+.....+((-1)^(n))/(n!)

n letters are written to n different persons and addresses on the n envelopes are also written. If the letters are placed in the envelopes at random,the probability that at least one letter is not placed in the right envelope,is (A) 1-(1)/(n) (B) 1-(1)/(2n) (C) 1-(1)/(n^(2))(D)1-(1)/(n!)

There are n letters and n addressed envelopes . If the letters are placed in the envelopes at random , what is the probability that all the letters are not placed in the right evelope ?

If n letters are placed at random in n addressed envelops then the probability that all the letters are placed in correct envelops is

If 5 letters are placed in 5 addressed envelopes and A,B,C defines the events that Exactly one letter is placed wrongly, atleast one placed wrongly, all are placed wrongly. Then the descending order of their probabilities is

A person write 4 letters and addresses 4 envelopes. If the letters are placed in the envelopes at random, then the probability that all letters are not placed in the right envelopes, is a. 1/4 b. 11/24 c. 15/24 d. 23/24