How many 3-digit numbers can be formed by using the digits 1 to 9 if no digit is repeated?

Explanation

To find the number of 3-digit numbers that can be formed using the digits from 1 to 9 without repeating any digits, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the available digits**: The digits available for use are 1, 2, 3, 4, 5, 6, 7, 8, and 9. This gives us a total of 9 digits.

2. **Choose the first digit**: For the first digit of the 3-digit number, we can choose any of the 9 digits. So, there are 9 options for the first digit.

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