Let's divide 63934874 by 21
The aim is to understand the frequency of 21 in 63934874.

Step 1:
The number 21 fits into 6 0 times, leaving a remainder of 6.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Deduct 0 from 6 and we're left with 6.
Bring next digit (3) of the dividend behind the 6 and repeat the process: 63 / 21

Step 2:
If we divide 63 by 21, we get 3 and a remainder of 0.
Use 3 as the next digit of our solution. 
Result so far: 3.0
Subtract 63 from 63 to get 0.
Fetch the next digit (9) from the dividend, attach it to 0 and continue: 9 / 21

Going ahead to step 3:
9 divided by 21 is 0 with a remainder of 9.
The number 0 becomes the next digit in our result. 
Result so far: 30.0
Subtracting 0 from 9 leaves us with 9.
Append the next digit (3) from the dividend to 9 and continue with: 93 / 21

Let's proceed to step 4:
93 divided by 21 is 4 with a remainder of 9.
Record the quotient 4 as the next digit in the result. 
Result so far: 304.0
The remainder is 9 after subtracting 84 from 93.
Bring next digit (4) of the dividend behind the 9 and repeat the process: 94 / 21

On to step 5:
21 can be fit into 94 4 times, resulting in a remainder of 10.
Record the quotient 4 as the next digit in the result. 
Result so far: 3044.0
Deduct 84 from 94 and we're left with 10.
Grab the next digit (8) from the dividend, add it to 10, then carry on: 108 / 21

Moving on to step 6:
21 goes into 108 5 times with a remainder of 3.
The number 5 becomes the next digit in our result. 
Result so far: 30445.0
The remainder is 3 after subtracting 105 from 108.
Include the next digit (7) from the dividend after 3, then repeat: 37 / 21

Moving on to step 7:
21 goes into 37 1 times with a remainder of 16.
Write down 1 as next digit of the result. 
Result so far: 304451.0
Subtract 21 from 37 to get 16.
Grab the next digit (4) from the dividend, add it to 16, then carry on: 164 / 21

Step 8:
The number 21 fits into 164 7 times, leaving a remainder of 17.
Put 7 as the next digit of the answer. 
Result so far: 3044517.0
Deduct 147 from 164 and we're left with 17.
Since there are no more digits in the dividend, we add a zero to the remainder making it 170, and continue the process.

Moving on to step 9:
21 can be fit into 170 8 times, resulting in a remainder of 2.
Record the quotient 8 as the next digit in the result. 
Result so far: 3044517.8
Deduct 168 from 170 and we're left with 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

Advancing to step 10:
20 divided by 21 is 0 with a remainder of 20.
Write down 0 as next digit of the result. 
Result so far: 3044517.8
The remainder is 20 after subtracting 0 from 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Advancing to step 11:
The number 21 fits into 200 9 times, leaving a remainder of 11.
Write down 9 as next digit of the result. 
Result so far: 3044517.809
If we take 189 away from 200, we end up with 11.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

Going ahead to step 12:
110 divided by 21 is 5 with a remainder of 5.
Use 5 as the next digit of our solution. 
Result so far: 3044517.8095
The remainder is 5 after subtracting 105 from 110.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

On to step 13:
When dividing 50 by 21, we get 2 with a remainder of 8.
The next digit of our result is 2. 
Result so far: 3044517.80952
If we subtract 42 from 50, we get 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Step 14:
The number 21 fits into 80 3 times, leaving a remainder of 17.
Record the quotient 3 as the next digit in the result. 
Result so far: 3044517.809523
Deduct 63 from 80 and we're left with 17.
Since there are no more digits in the dividend, we add a zero to the remainder making it 170, and continue the process.

Step 15:
If we divide 170 by 21, we get 8 and a remainder of 2.
Write down 8 as next digit of the result. 
Result so far: 3044517.8095238
Subtracting 168 from 170 leaves us with 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

Step 16:
20 divided by 21 is 0 with a remainder of 20.
Record the quotient 0 as the next digit in the result. 
Result so far: 3044517.8095238
Subtracting 0 from 20 leaves us with 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

The quotient of the division is 3044517.8095238, and the remainder is 2e-08.