Simplify :
67 + 13.85 - 29.904

Answer

To simplify the expression \( 67 + 13.85 - 29.904 \), we will follow these steps:

### Step 1: Convert all numbers to like decimals
We need to express all numbers with the same number of decimal places. The maximum decimal places in the numbers is 3 (from 29.904). Therefore, we convert:
- \( 67 \) to \( 67.000 \)
- \( 13.85 \) to \( 13.850 \)
- \( 29.904 \) remains \( 29.904 \)

So, we rewrite the expression as:
\[ 67.000 + 13.850 - 29.904 \]

### Step 2: Add the first two numbers
Now, we add \( 67.000 \) and \( 13.850 \):
\[ 67.000 + 13.850 = 80.850 \]

### Step 3: Subtract the third number
Next, we subtract \( 29.904 \) from \( 80.850 \):
\[ 80.850 - 29.904 \]

### Step 4: Perform the subtraction
Align the numbers for subtraction:
```
80.850
- 29.904
```
Now, we subtract starting from the rightmost digit:
- In the thousandths place: \( 0 - 4 \) (we need to borrow)
- In the hundredths place: \( 5 - 0 = 5 \)
- In the tenths place: \( 8 - 9 \) (we need to borrow)
- In the units place: \( 0 - 9 \) (we need to borrow)
- In the tens place: \( 7 - 2 = 5 \)

After borrowing and performing the subtraction, we get:
\[ 80.850 - 29.904 = 50.946 \]

### Final Answer
Thus, the simplified result is:
\[ \boxed{50.946} \]

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