Add the decimals:
28.9. 19.64, 123.697 and 0.354

Answer

To solve the problem of adding the decimals 28.9, 19.64, 123.697, and 0.354, we can follow these steps:

### Step-by-Step Solution:

1. **Align the Decimals**:
Write the numbers one below the other, aligning them by the decimal point. Fill in any missing decimal places with zeros to make them the same length.
```
28.900
19.640
123.697
0.354
```

2. **Add the Numbers**:
Start adding from the rightmost column (thousandths place) to the leftmost column (hundreds place).

- **Thousandths Place**:
\(0 + 0 + 7 + 4 = 11\) (write down 1 and carry over 1)
- **Hundredths Place**:
\(0 + 4 + 9 + 5 + 1 (carry) = 19\) (write down 9 and carry over 1)
- **Tenths Place**:
\(9 + 6 + 6 + 3 + 1 (carry) = 25\) (write down 5 and carry over 2)
- **Units Place**:
\(8 + 9 + 3 + 0 + 2 (carry) = 22\) (write down 2 and carry over 2)
- **Tens Place**:
\(2 + 1 + 2 (carry) = 5\) (write down 5)

So, when we add all the columns, we get:
```
28.900
19.640
123.697
0.354
+ ------------
172.591
```

3. **Final Result**:
The sum of 28.9, 19.64, 123.697, and 0.354 is **172.591**.