OK, let's do this. We've got 4260 and 5425 and we're adding them all together.

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

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

Step 3: We'll start by adding the digits 2 & 4 in column 3 and get 6.

Step 4: We'll start by adding the digits 4 & 5 in column 4 and get 9.

So, 4260 + 5425 = 9685.

