What comes just before `10000000` ?

Options

A. `9999997`
B. `9999998`
C. `9999999`
D. `9999996`

Answer

To find out what comes just before `10000000`, we need to subtract `1` from `10000000`. Let's go through the steps:

### Step 1: Write down the number
The number we are working with is:
\[ 10000000 \]

### Step 2: Subtract 1 from the number
Now, we will subtract `1` from `10000000`:
\[ 10000000 - 1 \]

### Step 3: Perform the subtraction
When we subtract `1`, we need to consider the digits:
- The last digit is `0`. Since we cannot subtract `1` from `0`, we will need to borrow from the next digit.
- The next digit is also `0`, and we will continue borrowing until we reach the first non-zero digit.

Here’s how it works:
1. Borrow from the first `1` (which is in the ten million place), turning it into `0` and making all the `0`s turn into `9`s.
2. After borrowing, we have:
- From `10000000`, it becomes `09999999`.

So, the calculation looks like this:
\[ 10000000 - 1 = 09999999 \]

### Step 4: Write the final answer
Thus, the number that comes just before `10000000` is:
\[ 9999999 \]

### Summary
The number just before `10000000` is `9999999`.

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