Multiply :
`10. 1001 xx 10. 01 `

Answer

To solve the multiplication of `10.1001` and `10.01`, we will follow these steps:

### Step 1: Remove the decimal points
First, we will ignore the decimal points and multiply the numbers as if they were whole numbers.

- `10.1001` becomes `101001`
- `10.01` becomes `1001`

### Step 2: Multiply the whole numbers
Now, we will multiply `101001` by `1001`.

```
101001
x 1001
__________
101001 (This is 101001 multiplied by 1)
+ 000000 (This is 101001 multiplied by 0, shifted one position to the left)
+ 101001 (This is 101001 multiplied by 1, shifted two positions to the left)
+ 000000 (This is 101001 multiplied by 0, shifted three positions to the left)
________________
101102001
```

### Step 3: Count the decimal places
Now we need to place the decimal point back in the result.

- In `10.1001`, there are 4 digits after the decimal point.
- In `10.01`, there are 2 digits after the decimal point.

So, the total number of decimal places is `4 + 2 = 6`.

### Step 4: Place the decimal point
We will place the decimal point in `101102001` such that there are 6 digits to the right of it.

- Starting from the right, we count 6 digits: `101.102001`.

### Final Answer
Thus, the final answer is:
```
10.1001 x 10.01 = 101.102001
```

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