A person writes 4 letters and addresses 4 envelopes If the letters are placed at random in the envelopes, - Maths - Probability

Question

A person writes 4 letters and addresses 4 envelopes If the
letters are placed at random in the envelopes, then the probability
that all the letters are not placed in the right envelopes is

Diksha Verma · Accepted Answer

Given: A person writes four letters and addresses four envelopes
then,Number of ways in which four letter can be placed in four envelopes=factorial 4 or 4×3×2×1There is exactly one way in which all letter can go correctly
∴ Required probability=4×3×2×1-14×3×2×1= 2324   Ans

A person writes 4 letters and addresses 4 envelopes. If the letters are placed at random in the envelopes, then the probability that all the letters are not placed in the right envelopes is