The number lock of a suitcase has 4 wheels, each labelled with ten digits i.e., from 0 to 9. The lock opens with a sequence of four digits with no repeats. What is the probability of a person getting the right sequence to open the suitcase?

Explanation

To find the probability of a person getting the right sequence to open the suitcase, we can follow these steps:

### Step 1: Determine the total number of possible sequences
The lock has 4 wheels, each labeled with the digits from 0 to 9. Since the sequence must have no repeated digits, we need to calculate how many different ways we can select and arrange 4 digits from the 10 available digits.

### Step 2: Calculate the number of ways to choose 4 digits from 10
We can choose 4 digits from 10 without repetition. The number of ways to choose 4 digits from 10 is given by the combination formula:

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