We've got two numbers: 5402 and 1091. Let's find their sum.

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

Step 2: We'll start by adding the digits 0 & 9 in column 2 and get 9.

Step 3: We'll start by adding the digits 4 & 0 in column 3 and get 4.

Step 4: We'll start by adding the digits 5 & 1 in column 4 and get 6.

So, 5402 + 1091 = 6493.

