Let's solve this addition problem. We have 168 and 4131, and we need to add them together.

Step 1: We'll start by adding the digits 8 & 1 in column 1 and get 9.

Step 2: We'll start by adding the digits 6 & 3 in column 2 and get 9.

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

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

So, 168 + 4131 = 4299.

