What should come in the following at the place of blank space ?
`0.001 xx0.01 = 0.1 +` ______

Options

A. `- 0.09999`
B. `-0.9909`
C. `-9.0009`
D. `-9.999`

Answer

To solve the equation \(0.001 \times 0.01 = 0.1 + \text{blank}\), we will follow these steps:

### Step 1: Calculate \(0.001 \times 0.01\)
First, we need to multiply the two decimal numbers:
\[ 0.001 \times 0.01 \]
To perform the multiplication, we can convert the decimals into fractions:
\[ 0.001 = \frac{1}{1000} \quad \text{and} \quad 0.01 = \frac{1}{100} \]
Now, multiply the fractions:
\[ \frac{1}{1000} \times \frac{1}{100} = \frac{1}{100000} = 0.00001 \]

### Step 2: Set up the equation
Now we have:
\[ 0.00001 = 0.1 + \text{blank} \]

### Step 3: Isolate the blank space
To find the value of the blank space, we need to rearrange the equation:
\[ \text{blank} = 0.00001 - 0.1 \]

### Step 4: Perform the subtraction
Now, we will perform the subtraction:
\[ 0.00001 - 0.1 \]
To do this, we can convert \(0.1\) into a decimal with the same number of decimal places as \(0.00001\):
\[ 0.1 = 0.10000 \]
Now we perform the subtraction:
\[ 0.00001 - 0.10000 = -0.09999 \]

### Conclusion
Thus, the value that should come in the blank space is:
\[ \text{blank} = -0.09999 \]

### Final Answer
The answer is \(-0.09999\).

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