We've got two numbers: 7854 and 9501. Let's find their sum.

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

Step 2: We'll start by adding the digits 5 & 0 in column 2 and get 5.

Step 3: We'll start by adding the digits 8 & 5 in column 3 and get 13.
We'll write down the last digit 3 and carry the 1 to the next column.

Step 4: We'll start by adding the digits 7 & 9 in column 4 and get 17.
We'll write down the last digit 7 and carry the 1 to the next column.

So, 7854 + 9501 = 17355.

