We look at the division of 709644 by 51 
The aim is to understand the frequency of 51 in 709644.

On to step 1:
51 can be fit into 7 0 times, resulting in a remainder of 7.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we subtract 0 from 7, we get 7.
Include the next digit (0) from the dividend after 7, then repeat: 70 / 51

Going ahead to step 2:
If we divide 70 by 51, we get 1 and a remainder of 19.
Put 1 as the next digit of the answer. 
Result so far: 1.0
Deduct 51 from 70 and we're left with 19.
Append the next digit (9) from the dividend to 19 and continue with: 199 / 51

Advancing to step 3:
When dividing 199 by 51, we get 3 with a remainder of 46.
The next digit of our result is 3. 
Result so far: 13.0
Deduct 153 from 199 and we're left with 46.
Fetch the next digit (6) from the dividend, attach it to 46 and continue: 466 / 51

Advancing to step 4:
51 goes into 466 9 times with a remainder of 7.
The number 9 becomes the next digit in our result. 
Result so far: 139.0
Subtract 459 from 466 to get 7.
Fetch the next digit (4) from the dividend, attach it to 7 and continue: 74 / 51

Advancing to step 5:
When dividing 74 by 51, we get 1 with a remainder of 23.
The number 1 becomes the next digit in our result. 
Result so far: 1391.0
The remainder is 23 after subtracting 51 from 74.
Take the next digit (4) from the dividend and append it to 23, then repeat: 234 / 51

Step 6:
51 goes into 234 4 times with a remainder of 30.
Put 4 as the next digit of the answer. 
Result so far: 13914.0
The remainder is 30 after subtracting 204 from 234.
Since there are no more digits in the dividend, we add a zero to the remainder making it 300, and continue the process.

Let's proceed to step 7:
51 can be fit into 300 5 times, resulting in a remainder of 45.
Record the quotient 5 as the next digit in the result. 
Result so far: 13914.5
If we take 255 away from 300, we end up with 45.
Since there are no more digits in the dividend, we add a zero to the remainder making it 450, and continue the process.

Advancing to step 8:
If we divide 450 by 51, we get 8 and a remainder of 42.
The next digit of our result is 8. 
Result so far: 13914.58
The remainder is 42 after subtracting 408 from 450.
Since there are no more digits in the dividend, we add a zero to the remainder making it 420, and continue the process.

Advancing to step 9:
The number 51 fits into 420 8 times, leaving a remainder of 12.
Write down 8 as next digit of the result. 
Result so far: 13914.588
If we subtract 408 from 420, we 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.

The quotient of the division is 13914.588, and the remainder is 0.0012.