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

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 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 ?

There are 4 envelopes corresponding to 4 letters. If the letters are placed in the envelopes at random, probability that all the letters are not placed in the right envelopes is

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

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