Let's divide 421230 by 8
We want to divide 421230 by 8.

Going ahead to step 1:
8 can be fit into 4 0 times, resulting in a remainder of 4.
The next digit of our result is 0. 
Result so far: 0.0
Subtracting 0 from 4 leaves us with 4.
Fetch the next digit (2) from the dividend, attach it to 4 and continue: 42 / 8

Step 2:
The number 8 fits into 42 5 times, leaving a remainder of 2.
Use 5 as the next digit of our solution. 
Result so far: 5.0
Subtract 40 from 42 to get 2.
Append the next digit (1) from the dividend to 2 and continue with: 21 / 8

Moving on to step 3:
8 can be fit into 21 2 times, resulting in a remainder of 5.
Use 2 as the next digit of our solution. 
Result so far: 52.0
Deduct 16 from 21 and we're left with 5.
Bring next digit (2) of the dividend behind the 5 and repeat the process: 52 / 8

Advancing to step 4:
8 can be fit into 52 6 times, resulting in a remainder of 4.
The next digit of our result is 6. 
Result so far: 526.0
Deduct 48 from 52 and we're left with 4.
Grab the next digit (3) from the dividend, add it to 4, then carry on: 43 / 8

Step 5:
8 can be fit into 43 5 times, resulting in a remainder of 3.
The number 5 becomes the next digit in our result. 
Result so far: 5265.0
If we take 40 away from 43, we end up with 3.
Take the next digit (0) from the dividend and append it to 3, then repeat: 30 / 8

Advancing to step 6:
When dividing 30 by 8, we get 3 with a remainder of 6.
Use 3 as the next digit of our solution. 
Result so far: 52653.0
Deduct 24 from 30 and we're left with 6.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

Going ahead to step 7:
If we divide 60 by 8, we get 7 and a remainder of 4.
The next digit of our result is 7. 
Result so far: 52653.7
If we subtract 56 from 60, we get 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Going ahead to step 8:
When dividing 40 by 8, we get 5 with a remainder of 0.
The next digit of our result is 5. 
Result so far: 52653.75
Subtracting 40 from 40 leaves us with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Moving on to step 9:
When dividing 0 by 8, we get 0 with a remainder of 0.
The number 0 becomes the next digit in our result. 
Result so far: 52653.75
If we subtract 0 from 0, we get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Step 10:
When dividing 0 by 8, we get 0 with a remainder of 0.
The next digit of our result is 0. 
Result so far: 52653.75
If we take 0 away from 0, we end up with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

The final result is 52653.75 with a remainder of 0.0.