`6888.009-487.999-87.989=?`

Options

A. 6000
B. 6570
C. 6430
D. 6310

Explanation

To solve the equation \(6888.009 - 487.999 - 87.989\), we will first approximate each number to make the calculations simpler.

### Step 1: Approximate each number
1. **Approximate 6888.009**:
- The decimal part is 0.009, which is less than 0.5. Therefore, we round down to 6888.

2. **Approximate 487.999**:
- The decimal part is 0.999, which is greater than 0.5. Therefore, we round up to 488.

3. **Approximate 87.989**:
- The decimal part is 0.989, which is also greater than 0.5. Therefore, we round up to 88.

### Step 2: Substitute the approximated values into the equation
Now we substitute the approximated values into the equation:
\[ 6888 - 488 - 88 \]

### Step 3: Perform the subtraction
1. First, subtract 488 from 6888:
\[ 6888 - 488 = 6400 \]

2. Next, subtract 88 from 6400:
\[ 6400 - 88 = 6312 \]

### Final Answer
Thus, the approximate value of \(6888.009 - 487.999 - 87.989\) is \(6312\).

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