Step 1: Write the second number under the first number so that the corresponding places are lined up.

Step 2: Add the ones column (7 + 6 = 13). Since 13 has two digits, both digits won't fit in the ones place. So, write the 3 in the ones place of the sum, and carry the 1 to the tens column. This is called regrouping.

Step 3: Add the tens column (1 + 7 + 8 = 16).
Since 16 has two digits, both digits won't fit in the tens place. So, write the 6 in the tens place of the sum, and carry the 1 to the hundreds column.

Step 4: Add the hundreds column (1 + 0 + 7 = 8). Write the 8 in the hundreds place of the sum.

Step 5: Add the thousands column (3 + 4 = 7). Write the 7 in the thousands place of the sum.

Step 6: Add the ten thousands column (5 + 7 = 12).
Since 12 has two digits, both digits won't fit in the ten thousands place. So, write the 2 in the ten thousands place of the sum, and carry the 1 to the hundred thousands column.

Step 7: Add the hundred thousands column (1 + 2 + 1 = 4). Write the 4 in the hundred thousands place of the sum.

Step 1: Write the second number under the first number so that the corresponding places are lined up.

Step 2: Subtract the ones column (6 - 5 = 1). Write the 1 in the ones place of the difference.

Step 3: Look at the tens column. 1 is less than 9, so take 1 hundred from the hundreds place, change the hundred to 10 tens, and add the 10 tens to the tens place. This is called regrouping.
Then, subtract the ones column (11 - 9 = 2). Write the 2 in the tens place of the difference.

Step 4: Subtract the hundreds column (2 - 2 = 0). Write the 0 in the hundreds place of the difference.

Step 5: Look at the thousands column. 3 is less than 4, so take 1 ten thousand from the ten thousands place, change the ten thousand to 10 thousands, and add the 10 thousands to the thousands place. Then, subtract the thousands column (13 - 4 = 9). Write the 9 in the thousands place of the difference.

Step 6: Subtract the ten thousands column (7 - 0 = 7). Write the 7 in the ten thousands place of the difference.

Step 7: Subtract the hundred thousands column (7 - 4 = 3). Write the 3 in the hundred thousands place of the difference.