Find the product of :
smallest 5-digit number and greatest 4-digit number.

Answer

To solve the problem of finding the product of the smallest 5-digit number and the greatest 4-digit number, we will follow these steps:

### Step 1: Identify the smallest 5-digit number
The smallest 5-digit number is 10,000.

### Step 2: Identify the greatest 4-digit number
The greatest 4-digit number is 9,999.

### Step 3: Set up the multiplication
We need to multiply the two numbers we identified:
\[ 10,000 \times 9,999 \]

### Step 4: Perform the multiplication
To calculate this product, we can break it down:
1. First, multiply 9,999 by 1 (the leading digit of 10,000):
\[ 9,999 \times 1 = 9,999 \]

2. Next, since 10,000 has four zeros, we will append these four zeros to the result:
\[ 9,999 \text{ becomes } 9,999,0000 \]

### Step 5: Write the final answer
Thus, the product of the smallest 5-digit number and the greatest 4-digit number is:
\[ 99,990,000 \]

### Summary of the solution:
The product of the smallest 5-digit number (10,000) and the greatest 4-digit number (9,999) is:
\[ 99,990,000 \]

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