We have numbers 4007 and 51. Let's start adding them together.

Step 1: We'll start by adding the digits 7 & 1 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 & 0 in column 3 and get 0.

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

So, 4007 + 51 = 4058.

