Find the number of ways in which one can post 5 letters in 7letter boxes.

Explanation

To find the number of ways to post 5 letters into 7 letter boxes, we can follow these steps:

### Step 1: Understand the Problem
We have 5 letters and 7 boxes. Each letter can be placed in any of the 7 boxes. There are no restrictions on how many letters can go into each box.

**Hint:** Think about how many choices you have for each letter.

### Step 2: Determine Choices for Each Letter
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