420147 divided by 51 
The aim is to understand the frequency of 51 in 420147.

Moving on to step 1:
4 divided by 51 is 0 with a remainder of 4.
Write down 0 as next digit of the result. 
Result so far: 0.0
Deduct 0 from 4 and we're left with 4.
Take the next digit (2) from the dividend and append it to 4, then repeat: 42 / 51

On to step 2:
If we divide 42 by 51, we get 0 and a remainder of 42.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we subtract 0 from 42, we get 42.
Take the next digit (0) from the dividend and append it to 42, then repeat: 420 / 51

Moving on to step 3:
The number 51 fits into 420 8 times, leaving a remainder of 12.
Use 8 as the next digit of our solution. 
Result so far: 8.0
The remainder is 12 after subtracting 408 from 420.
Grab the next digit (1) from the dividend, add it to 12, then carry on: 121 / 51

Going ahead to step 4:
51 goes into 121 2 times with a remainder of 19.
Record the quotient 2 as the next digit in the result. 
Result so far: 82.0
Subtract 102 from 121 to get 19.
Bring next digit (4) of the dividend behind the 19 and repeat the process: 194 / 51

Advancing to step 5:
The number 51 fits into 194 3 times, leaving a remainder of 41.
The next digit of our result is 3. 
Result so far: 823.0
Subtracting 153 from 194 leaves us with 41.
Fetch the next digit (7) from the dividend, attach it to 41 and continue: 417 / 51

Advancing to step 6:
The number 51 fits into 417 8 times, leaving a remainder of 9.
The next digit of our result is 8. 
Result so far: 8238.0
Subtract 408 from 417 to get 9.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

Advancing to step 7:
51 goes into 90 1 times with a remainder of 39.
Write down 1 as next digit of the result. 
Result so far: 8238.1
Subtract 51 from 90 to get 39.
Since there are no more digits in the dividend, we add a zero to the remainder making it 390, and continue the process.

Moving on to step 8:
When dividing 390 by 51, we get 7 with a remainder of 33.
The number 7 becomes the next digit in our result. 
Result so far: 8238.17
The remainder is 33 after subtracting 357 from 390.
Since there are no more digits in the dividend, we add a zero to the remainder making it 330, and continue the process.

Let's proceed to step 9:
When dividing 330 by 51, we get 6 with a remainder of 24.
Use 6 as the next digit of our solution. 
Result so far: 8238.176
The remainder is 24 after subtracting 306 from 330.
Since there are no more digits in the dividend, we add a zero to the remainder making it 240, and continue the process.

On to step 10:
If we divide 240 by 51, we get 4 and a remainder of 36.
Put 4 as the next digit of the answer. 
Result so far: 8238.1764
If we subtract 204 from 240, we get 36.
Since there are no more digits in the dividend, we add a zero to the remainder making it 360, and continue the process.

Going ahead to step 11:
51 goes into 360 7 times with a remainder of 3.
Record the quotient 7 as the next digit in the result. 
Result so far: 8238.17647
If we take 357 away from 360, 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.

Step 12:
The number 51 fits into 30 0 times, leaving a remainder of 30.
Use 0 as the next digit of our solution. 
Result so far: 8238.17647
Subtracting 0 from 30 leaves us with 30.
Since there are no more digits in the dividend, we add a zero to the remainder making it 300, and continue the process.

Going ahead to step 13:
300 divided by 51 is 5 with a remainder of 45.
Write down 5 as next digit of the result. 
Result so far: 8238.1764705
Subtract 255 from 300 to get 45.
Since there are no more digits in the dividend, we add a zero to the remainder making it 450, and continue the process.

Step 14:
51 can be fit into 450 8 times, resulting in a remainder of 42.
Record the quotient 8 as the next digit in the result. 
Result so far: 8238.17647058
If we subtract 408 from 450, we get 42.
Since there are no more digits in the dividend, we add a zero to the remainder making it 420, and continue the process.

The quotient of the division is 8238.17647058, and the remainder is 4.2e-08.