﻿ A person writes 4 letters and addresses on 4 envelopes. If the letters are placed in the envelopes at random, the probability that not all letters are placed in correct envelopes is : Kaysons Education

# A Person Writes 4 Letters And Addresses On 4 Envelopes. If The Letters Are Placed In The Envelopes At Random, The Probability That Not All Letters Are Placed In Correct Envelopes Is

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## Question

### Solution

Correct option is

23/24

Required probability

= 1 – P (all the letters are put is correct envelops)

The numbers of ways of putting the letters in the envelops

The number of ways of putting letters in correct envelops = 1

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