Okay, we are given 8742 and 47. Let's add them up step by step.

Step 1: We'll start by adding the digits 2 & 7 in column 1 and get 9.

Step 2: We'll start by adding the digits 4 & 4 in column 2 and get 8.

Step 3: We'll start by adding the digits 7 & 0 in column 3 and get 7.

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

So, 8742 + 47 = 8789.

