561939 ÷ 51 
The aim is to understand the frequency of 51 in 561939.

Going ahead to step 1:
51 goes into 5 0 times with a remainder of 5.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtract 0 from 5 to get 5.
Bring next digit (6) of the dividend behind the 5 and repeat the process: 56 / 51

On to step 2:
56 divided by 51 is 1 with a remainder of 5.
The next digit of our result is 1. 
Result so far: 1.0
Subtracting 51 from 56 leaves us with 5.
Grab the next digit (1) from the dividend, add it to 5, then carry on: 51 / 51

Going ahead to step 3:
When dividing 51 by 51, we get 1 with a remainder of 0.
The number 1 becomes the next digit in our result. 
Result so far: 11.0
Subtract 51 from 51 to get 0.
Append the next digit (9) from the dividend to 0 and continue with: 9 / 51

Moving on to step 4:
When dividing 9 by 51, we get 0 with a remainder of 9.
Put 0 as the next digit of the answer. 
Result so far: 110.0
Subtract 0 from 9 to get 9.
Include the next digit (3) from the dividend after 9, then repeat: 93 / 51

Going ahead to step 5:
93 divided by 51 is 1 with a remainder of 42.
Write down 1 as next digit of the result. 
Result so far: 1101.0
Subtracting 51 from 93 leaves us with 42.
Append the next digit (9) from the dividend to 42 and continue with: 429 / 51

Going ahead to step 6:
51 can be fit into 429 8 times, resulting in a remainder of 21.
Use 8 as the next digit of our solution. 
Result so far: 11018.0
Subtract 408 from 429 to get 21.
Since there are no more digits in the dividend, we add a zero to the remainder making it 210, and continue the process.

Going ahead to step 7:
210 divided by 51 is 4 with a remainder of 6.
The next digit of our result is 4. 
Result so far: 11018.4
Subtract 204 from 210 to get 6.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

Going ahead to step 8:
51 goes into 60 1 times with a remainder of 9.
Use 1 as the next digit of our solution. 
Result so far: 11018.41
Deduct 51 from 60 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.

Going ahead to step 9:
When dividing 90 by 51, we get 1 with a remainder of 39.
The next digit of our result is 1. 
Result so far: 11018.411
If we take 51 away from 90, we end up with 39.
Since there are no more digits in the dividend, we add a zero to the remainder making it 390, and continue the process.

Our division results in 11018.411 with a remaining 0.0039.