OK, let's do this. We've got 2542 and 5241 and we're adding them all together.

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

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 5 & 2 in column 3 and get 7.

Step 4: We'll start by adding the digits 2 & 5 in column 4 and get 7.

So, 2542 + 5241 = 7783.

