How many numbers lying between 100 and 1000 can be formed with the digits 0, 1, 2, 3, 4, 5, if the repetition of the digits is not allowed?

Explanation

To solve the problem of how many numbers lying between 100 and 1000 can be formed using the digits 0, 1, 2, 3, 4, and 5 without repetition, we can follow these steps:

### Step 1: Identify the structure of the numbers
We need to form 3-digit numbers that lie between 100 and 1000. This means the first digit (hundreds place) cannot be 0.

### Step 2: Choose the first digit
The possible choices for the first digit (hundreds place) are 1, 2, 3, 4, and 5 (since 0 cannot be used). This gives us 5 options.

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