If three letters can be posted to any one of the 5 different addresses, then the probability that the three letters are posted to exactly two addresses is :
Solution
<p>We have 3 letters and 5 addresses, where 3 letters are posted to exactly 2 addresses. First, we will select 2 addresses in ${ }^5 C_2$ ways.</p>
<p>Now, 3 letters can be posted to exactly 2 addresses in 6 ways.</p>
<p>$$\begin{aligned}
\therefore \text { Probability }=\frac{{ }^5 C_2 \times 6}{5^3} & \\
& =\frac{60}{125}=\frac{12}{25}
\end{aligned}$$</p>
About this question
Subject: Mathematics · Chapter: Probability · Topic: Classical and Axiomatic Probability
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