We've got two numbers: 3 and 2151. Let's find their sum.

Step 1: We'll start by adding the digits 3 & 1 in column 1 and get 4.

Step 2: We'll start by adding the digits 0 & 5 in column 2 and get 5.

Step 3: We'll start by adding the digits 0 & 1 in column 3 and get 1.

Step 4: We'll start by adding the digits 0 & 2 in column 4 and get 2.

So, 3 + 2151 = 2154.

