Sum of the greatest 8 digit number and the smallest 9 digit number is

Options

A. 19999999
B. 199999999
C. 999999999
D. 10000999

Answer

To find the sum of the greatest 8-digit number and the smallest 9-digit number, we can follow these steps:

### Step 1: Identify the greatest 8-digit number
The greatest 8-digit number is formed by using the digit '9' in all 8 places. Therefore, the greatest 8-digit number is:
\[ 99999999 \]

### Step 2: Identify the smallest 9-digit number
The smallest 9-digit number is formed by placing '1' in the first position (the most significant digit) and '0' in all the remaining positions. Therefore, the smallest 9-digit number is:
\[ 100000000 \]

### Step 3: Add the two numbers together
Now, we will add the greatest 8-digit number and the smallest 9-digit number:
\[ 99999999 + 100000000 \]

### Step 4: Perform the addition
Align the numbers for addition:
```
99999999
[phone]
-----------
199999999
```

Thus, the sum of the greatest 8-digit number and the smallest 9-digit number is:
\[ 199999999 \]

### Final Answer:
The required sum is \( 199999999 \).

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