Solve them using suitable rearrangement.
`243 + 621 + 357`

Answer

To solve the problem \(243 + 621 + 357\) using suitable rearrangement, we can follow these steps:

### Step 1: Rearrangement
We will rearrange the numbers to make the addition easier. We can add \(243\) and \(357\) first.

\[ 243 + 357 \]

### Step 2: Add \(243\) and \(357\)
Now, we will add these two numbers together.

\[ 243 + 357 = 600 \]

- **Calculation**:
- Units place: \(3 + 7 = 10\) (write down \(0\) and carry over \(1\))
- Tens place: \(4 + 5 + 1 = 10\) (write down \(0\) and carry over \(1\))
- Hundreds place: \(2 + 3 + 1 = 6\)

So, \(243 + 357 = 600\).

### Step 3: Add the result to \(621\)
Now we will add \(600\) to \(621\).

\[ 600 + 621 \]

### Step 4: Perform the addition
Now, we will add these two numbers together.

\[ 600 + 621 = 1221 \]

- **Calculation**:
- Units place: \(0 + 1 = 1\)
- Tens place: \(0 + 2 = 2\)
- Hundreds place: \(6 + 6 = 12\) (write down \(2\) and carry over \(1\))
- Thousands place: \(1\) (from the carry)

So, \(600 + 621 = 1221\).

### Final Answer
Thus, the final answer is:

\[ \boxed{1221} \]

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