Let's divide 353425 by 21
We want to figure out the number of times 353425 can be divided by 21.

Advancing to step 1:
When dividing 3 by 21, we get 0 with a remainder of 3.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtracting 0 from 3 leaves us with 3.
Bring next digit (5) of the dividend behind the 3 and repeat the process: 35 / 21

Moving on to step 2:
35 divided by 21 is 1 with a remainder of 14.
Write down 1 as next digit of the result. 
Result so far: 1.0
If we take 21 away from 35, we end up with 14.
Fetch the next digit (3) from the dividend, attach it to 14 and continue: 143 / 21

Moving on to step 3:
If we divide 143 by 21, we get 6 and a remainder of 17.
Record the quotient 6 as the next digit in the result. 
Result so far: 16.0
If we subtract 126 from 143, we get 17.
Append the next digit (4) from the dividend to 17 and continue with: 174 / 21

On to step 4:
If we divide 174 by 21, we get 8 and a remainder of 6.
Use 8 as the next digit of our solution. 
Result so far: 168.0
If we take 168 away from 174, we end up with 6.
Include the next digit (2) from the dividend after 6, then repeat: 62 / 21

On to step 5:
The number 21 fits into 62 2 times, leaving a remainder of 20.
The number 2 becomes the next digit in our result. 
Result so far: 1682.0
The remainder is 20 after subtracting 42 from 62.
Append the next digit (5) from the dividend to 20 and continue with: 205 / 21

Advancing to step 6:
205 divided by 21 is 9 with a remainder of 16.
Record the quotient 9 as the next digit in the result. 
Result so far: 16829.0
If we take 189 away from 205, we end up with 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

Let's proceed to step 7:
160 divided by 21 is 7 with a remainder of 13.
Record the quotient 7 as the next digit in the result. 
Result so far: 16829.7
The remainder is 13 after subtracting 147 from 160.
Since there are no more digits in the dividend, we add a zero to the remainder making it 130, and continue the process.

Going ahead to step 8:
21 can be fit into 130 6 times, resulting in a remainder of 4.
Put 6 as the next digit of the answer. 
Result so far: 16829.76
If we subtract 126 from 130, 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.

Let's proceed to step 9:
40 divided by 21 is 1 with a remainder of 19.
Use 1 as the next digit of our solution. 
Result so far: 16829.761
Subtracting 21 from 40 leaves us with 19.
Since there are no more digits in the dividend, we add a zero to the remainder making it 190, and continue the process.

Going ahead to step 10:
When dividing 190 by 21, we get 9 with a remainder of 1.
Put 9 as the next digit of the answer. 
Result so far: 16829.7619
The remainder is 1 after subtracting 189 from 190.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

Let's proceed to step 11:
21 goes into 10 0 times with a remainder of 10.
The number 0 becomes the next digit in our result. 
Result so far: 16829.7619
If we subtract 0 from 10, we get 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Advancing to step 12:
When dividing 100 by 21, we get 4 with a remainder of 16.
The number 4 becomes the next digit in our result. 
Result so far: 16829.761904
If we subtract 84 from 100, we get 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

Step 13:
160 divided by 21 is 7 with a remainder of 13.
The next digit of our result is 7. 
Result so far: 16829.7619047
Deduct 147 from 160 and we're left with 13.
Since there are no more digits in the dividend, we add a zero to the remainder making it 130, and continue the process.

Step 14:
130 divided by 21 is 6 with a remainder of 4.
Put 6 as the next digit of the answer. 
Result so far: 16829.76190476
If we take 126 away from 130, we end up with 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Our division results in 16829.76190476 with a remaining 4e-09.