Add the decimals:
18.6. 84.75, 8.345 and 9.7

Answer

To solve the problem of adding the decimals 18.6, 84.75, 8.345, and 9.7, we will follow these steps:

### Step 1: Align the decimals
First, we need to write the numbers one below the other, aligning the decimal points. We can also fill in any empty spaces with zeros to make it easier to add.

```
18.600
84.750
8.345
9.700
```

### Step 2: Add the numbers column by column
Now we will add the numbers starting from the rightmost column (the thousandths place) and moving to the left.

1. **Thousandths place**:
- 0 + 0 + 5 + 0 = 5

2. **Hundredths place**:
- 0 + 5 + 4 + 0 = 9

3. **Tenths place**:
- 6 + 7 + 3 + 7 = 23 (write down 3 and carry over 2)

4. **Units place**:
- 8 + 4 + 8 + 9 + 2 (carry) = 31 (write down 1 and carry over 3)

5. **Tens place**:
- 1 + 8 + 0 + 0 + 3 (carry) = 12 (write down 2 and carry over 1)

6. **Hundreds place**:
- 0 + 0 + 0 + 0 + 1 (carry) = 1

### Step 3: Write the final answer
Putting it all together, we have:

```
18.600
84.750
8.345
9.700
__________
121.395
```

So, the sum of 18.6, 84.75, 8.345, and 9.7 is **121.395**.

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