Let's divide 149910 by 21
Our goal is to divide 149910 by 21.

Advancing to step 1:
21 goes into 1 0 times with a remainder of 1.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we subtract 0 from 1, we get 1.
Append the next digit (4) from the dividend to 1 and continue with: 14 / 21

Advancing to step 2:
The number 21 fits into 14 0 times, leaving a remainder of 14.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtract 0 from 14 to get 14.
Bring next digit (9) of the dividend behind the 14 and repeat the process: 149 / 21

Moving on to step 3:
When dividing 149 by 21, we get 7 with a remainder of 2.
Record the quotient 7 as the next digit in the result. 
Result so far: 7.0
Subtract 147 from 149 to get 2.
Include the next digit (9) from the dividend after 2, then repeat: 29 / 21

Advancing to step 4:
The number 21 fits into 29 1 times, leaving a remainder of 8.
The number 1 becomes the next digit in our result. 
Result so far: 71.0
Deduct 21 from 29 and we're left with 8.
Grab the next digit (1) from the dividend, add it to 8, then carry on: 81 / 21

Let's proceed to step 5:
81 divided by 21 is 3 with a remainder of 18.
Record the quotient 3 as the next digit in the result. 
Result so far: 713.0
If we take 63 away from 81, we end up with 18.
Fetch the next digit (0) from the dividend, attach it to 18 and continue: 180 / 21

On to step 6:
When dividing 180 by 21, we get 8 with a remainder of 12.
The number 8 becomes the next digit in our result. 
Result so far: 7138.0
Subtracting 168 from 180 leaves us with 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

On to step 7:
When dividing 120 by 21, we get 5 with a remainder of 15.
Use 5 as the next digit of our solution. 
Result so far: 7138.5
Deduct 105 from 120 and we're left with 15.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

Going ahead to step 8:
21 can be fit into 150 7 times, resulting in a remainder of 3.
The next digit of our result is 7. 
Result so far: 7138.57
If we subtract 147 from 150, we get 3.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

Let's proceed to step 9:
When dividing 30 by 21, we get 1 with a remainder of 9.
The number 1 becomes the next digit in our result. 
Result so far: 7138.571
The remainder is 9 after subtracting 21 from 30.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

On to step 10:
If we divide 90 by 21, we get 4 and a remainder of 6.
Use 4 as the next digit of our solution. 
Result so far: 7138.5714
Subtracting 84 from 90 leaves us 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 11:
If we divide 60 by 21, we get 2 and a remainder of 18.
Record the quotient 2 as the next digit in the result. 
Result so far: 7138.57142
If we take 42 away from 60, we end up with 18.
Since there are no more digits in the dividend, we add a zero to the remainder making it 180, and continue the process.

Let's proceed to step 12:
When dividing 180 by 21, we get 8 with a remainder of 12.
Put 8 as the next digit of the answer. 
Result so far: 7138.571428
If we take 168 away from 180, we end up with 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Step 13:
When dividing 120 by 21, we get 5 with a remainder of 15.
Write down 5 as next digit of the result. 
Result so far: 7138.5714285
Subtract 105 from 120 to get 15.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

Step 14:
If we divide 150 by 21, we get 7 and a remainder of 3.
Use 7 as the next digit of our solution. 
Result so far: 7138.57142857
If we take 147 away from 150, we end up with 3.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

After the division, we end up with 7138.57142857 and a remainder of 3e-09.