The sum of 609.20`+`16.3`+`42 is `"_____________"`

Options

A. 660.5
B. 667.5
C. 669.5
D. 670.5

Answer

To find the sum of the numbers 609.20, 16.3, and 42, we will follow these steps:

### Step 1: Align the numbers by their decimal points
We write the numbers one below the other, aligning them at the decimal point. Since the numbers have different decimal places, we can add zeros to the end of the decimal places to make them equal.

```
609.20
+ 16.30
+ 42.00
```

### Step 2: Add the numbers column by column
We start adding from the rightmost column (the decimal part) and move to the left.

1. **Decimal Place**:
- 0 + 0 + 0 = 0

2. **Tenths Place**:
- 2 + 3 + 0 = 5

3. **Units Place**:
- 9 + 6 + 2 = 17
- Write down 7 and carry over 1.

4. **Tens Place**:
- 0 (from carry) + 0 + 1 (carry) + 4 = 6

5. **Hundreds Place**:
- 6 + 0 + 0 = 6

Now we can write down the sum:

```
609.20
+ 16.30
+ 42.00
__________
667.50
```

### Final Result
The sum of 609.20 + 16.3 + 42 is **667.50**.

---