Okay, we are given 4000 and 2158. Let's add them up step by step.

Step 1: We'll start by adding the digits 0 & 8 in column 1 and get 8.

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 4 & 2 in column 4 and get 6.

So, 4000 + 2158 = 6158.

