Let's get this math done. We have 840 and 461 and we're going to add them all together.

Step 1: We'll start by adding the digits 0 & 1 in column 1 and get 1.

Step 2: We'll start by adding the digits 4 & 6 in column 2 and get 10.
We'll write down the last digit 0 and carry the 1 to the next column.

Step 3: We'll start by adding the digits 8 & 4 in column 3 and get 13.
We'll write down the last digit 3 and carry the 1 to the next column.

So, 840 + 461 = 1301.

