Okay, we are given 153 and 8308. Let's add them up step by step.

Step 1: We'll start by adding the digits 3 & 8 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 5 & 0 in column 2 and get 6.

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

Step 4: We'll start by adding the digits 0 & 8 in column 4 and get 8.

So, 153 + 8308 = 8461.

