Three letters can be posted in five letter boxes in `3^(5)` ways.

Explanation

To solve the problem of how many ways three letters can be posted in five letter boxes, we can break it down step by step.

### Step 1: Understand the Problem
We have three letters (let's call them L1, L2, and L3) and five letter boxes (let's denote them as B1, B2, B3, B4, and B5). Each letter can be placed in any of the five boxes.

### Step 2: Determine Choices for Each Letter
For each letter, we have 5 choices (the 5 letter boxes).

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