Let's divide 70890 by 21
We want to figure out the number of times 70890 can be divided by 21.

Going ahead to step 1:
If we divide 7 by 21, we get 0 and a remainder of 7.
The next digit of our result is 0. 
Result so far: 0.0
The remainder is 7 after subtracting 0 from 7.
Fetch the next digit (0) from the dividend, attach it to 7 and continue: 70 / 21

Let's proceed to step 2:
If we divide 70 by 21, we get 3 and a remainder of 7.
The number 3 becomes the next digit in our result. 
Result so far: 3.0
Subtracting 63 from 70 leaves us with 7.
Include the next digit (8) from the dividend after 7, then repeat: 78 / 21

Let's proceed to step 3:
When dividing 78 by 21, we get 3 with a remainder of 15.
Record the quotient 3 as the next digit in the result. 
Result so far: 33.0
If we take 63 away from 78, we end up with 15.
Take the next digit (9) from the dividend and append it to 15, then repeat: 159 / 21

Step 4:
When dividing 159 by 21, we get 7 with a remainder of 12.
Use 7 as the next digit of our solution. 
Result so far: 337.0
Subtract 147 from 159 to get 12.
Append the next digit (0) from the dividend to 12 and continue with: 120 / 21

Advancing to step 5:
21 can be fit into 120 5 times, resulting in a remainder of 15.
Record the quotient 5 as the next digit in the result. 
Result so far: 3375.0
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.

Going ahead to step 6:
150 divided by 21 is 7 with a remainder of 3.
Put 7 as the next digit of the answer. 
Result so far: 3375.7
Subtract 147 from 150 to 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.

Going ahead to step 7:
21 can be fit into 30 1 times, resulting in a remainder of 9.
The number 1 becomes the next digit in our result. 
Result so far: 3375.71
Deduct 21 from 30 and we're left with 9.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

Moving on to step 8:
The number 21 fits into 90 4 times, leaving a remainder of 6.
The number 4 becomes the next digit in our result. 
Result so far: 3375.714
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.

Let's proceed to step 9:
If we divide 60 by 21, we get 2 and a remainder of 18.
Put 2 as the next digit of the answer. 
Result so far: 3375.7142
Deduct 42 from 60 and we're left 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.

Step 10:
21 goes into 180 8 times with a remainder of 12.
Record the quotient 8 as the next digit in the result. 
Result so far: 3375.71428
Subtract 168 from 180 to get 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Moving on to step 11:
If we divide 120 by 21, we get 5 and a remainder of 15.
The number 5 becomes the next digit in our result. 
Result so far: 3375.714285
The remainder is 15 after subtracting 105 from 120.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

Moving on to step 12:
150 divided by 21 is 7 with a remainder of 3.
The next digit of our result is 7. 
Result so far: 3375.7142857
The remainder is 3 after subtracting 147 from 150.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

On to step 13:
30 divided by 21 is 1 with a remainder of 9.
Write down 1 as next digit of the result. 
Result so far: 3375.71428571
Deduct 21 from 30 and we're left with 9.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

The quotient of the division is 3375.71428571, and the remainder is 9e-09.