Let's break this down. We're going to add 1237 and 9014 together.

Step 1: We'll start by adding the digits 7 & 4 in column 1 and get 11.
We'll write down the last digit 1 and carry the 1 to the next column.

Step 2: We'll start by adding the digits 3 & 1 in column 2 and get 5.

Step 3: We'll start by adding the digits 2 & 0 in column 3 and get 2.

Step 4: We'll start by adding the digits 1 & 9 in column 4 and get 10.
We'll write down the last digit 0 and carry the 1 to the next column.

So, 1237 + 9014 = 10251.

