There are `n` letters and `n` addressed envelopes. Find the probability that all the letters are not kept in the right envelope.

There are 4 letters and 4 addressed envelopes. Find the probability that all the letters are not dispatched in right envelopes.

There are 6 letters and 6 addressed envelopes. Find the probability that at least one letter goes into the wrong envelope.

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 ?

Three letters, to each of which corresponds an envelope, are placed in the envelopes at random. The probability that all the letters are not placed in the right envelopes, 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

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

There are four letters and four directed envelopes. The number of ways in which all the letters can be put in the wrong envelope is a. 8 b. 9 c. 16 d. none of these

Three letters are written to different persons , and the addresses on the three envelopes are also written . Without looking at the addresses , find the probability that the letters go into the right envelopes .

Two letters are drawn from the english alphabets. Find the probability that both letters are vowels.

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