Let's get this math done. We have 5172 and 1527 and we're going to add them all together.

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 7 & 2 in column 2 and get 9.

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

Step 4: We'll start by adding the digits 5 & 1 in column 4 and get 6.

So, 5172 + 1527 = 6699.

