Find the product of :
greatest 3-digit number and smallest 5-digit number.

Answer

To find the product of the greatest 3-digit number and the smallest 5-digit number, follow these steps:

### Step 1: Identify the greatest 3-digit number
The greatest 3-digit number is 999.

### Step 2: Identify the smallest 5-digit number
The smallest 5-digit number is 10000.

### Step 3: Set up the multiplication
We need to multiply the two numbers:
\[ 999 \times 10000 \]

### Step 4: Simplify the multiplication
To multiply 999 by 10000, we can break it down:
- First, multiply 999 by 1 (the first digit of 10000):
\[ 999 \times 1 = 999 \]

### Step 5: Add the zeros
Since 10000 has 4 zeros, we will add 4 zeros to the result from Step 4:
\[ 999 \times 10000 = 9990000 \]

### Final Answer
The product of the greatest 3-digit number and the smallest 5-digit number is:
\[ 9990000 \]

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