Using the arrangements formula, considering the given digits, it is found that Edward writes 6 numbers.
<h3>What is the arrangements formula?</h3>The number of possible arrangements of n elements is given by the factorial of n, that is:
In this problem, the first digit has to be 5, while the other three are arranged, hence the total number of arrangements is given by:
More can be learned about the arrangements formula at brainly.com/question/25925367
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