How many different signals can be given using any number of flags from 4 flags of different colours?

Explanation

To solve the problem of how many different signals can be given using any number of flags from 4 flags of different colors, we can break it down step by step.

### Step-by-Step Solution:

1. **Understanding the Problem**: We have 4 flags of different colors, and we can use any number of these flags (from 1 to 4) to create signals.

2. **Using Permutations**: Since the order in which we arrange the flags matters (as different arrangements represent different signals), we will use permutations to calculate the number of different signals for each possible number of flags used.

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