We're dividing 51801993 by 430 
The aim is to understand the frequency of 430 in 51801993.

Advancing to step 1:
5 divided by 430 is 0 with a remainder of 5.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Deduct 0 from 5 and we're left with 5.
Fetch the next digit (1) from the dividend, attach it to 5 and continue: 51 / 430

On to step 2:
430 goes into 51 0 times with a remainder of 51.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtracting 0 from 51 leaves us with 51.
Fetch the next digit (8) from the dividend, attach it to 51 and continue: 518 / 430

Moving on to step 3:
When dividing 518 by 430, we get 1 with a remainder of 88.
Record the quotient 1 as the next digit in the result. 
Result so far: 1.0
If we take 430 away from 518, we end up with 88.
Grab the next digit (0) from the dividend, add it to 88, then carry on: 880 / 430

Going ahead to step 4:
430 goes into 880 2 times with a remainder of 20.
The number 2 becomes the next digit in our result. 
Result so far: 12.0
If we subtract 860 from 880, we get 20.
Take the next digit (1) from the dividend and append it to 20, then repeat: 201 / 430

Moving on to step 5:
430 goes into 201 0 times with a remainder of 201.
Write down 0 as next digit of the result. 
Result so far: 120.0
If we take 0 away from 201, we end up with 201.
Append the next digit (9) from the dividend to 201 and continue with: 2019 / 430

Let's proceed to step 6:
2019 divided by 430 is 4 with a remainder of 299.
Put 4 as the next digit of the answer. 
Result so far: 1204.0
Deduct 1720 from 2019 and we're left with 299.
Grab the next digit (9) from the dividend, add it to 299, then carry on: 2999 / 430

Let's proceed to step 7:
If we divide 2999 by 430, we get 6 and a remainder of 419.
The number 6 becomes the next digit in our result. 
Result so far: 12046.0
If we take 2580 away from 2999, we end up with 419.
Grab the next digit (3) from the dividend, add it to 419, then carry on: 4193 / 430

On to step 8:
The number 430 fits into 4193 9 times, leaving a remainder of 323.
The next digit of our result is 9. 
Result so far: 120469.0
If we take 3870 away from 4193, we end up with 323.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3230, and continue the process.

On to step 9:
If we divide 3230 by 430, we get 7 and a remainder of 220.
Put 7 as the next digit of the answer. 
Result so far: 120469.7
If we subtract 3010 from 3230, we get 220.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2200, and continue the process.

Moving on to step 10:
The number 430 fits into 2200 5 times, leaving a remainder of 50.
The next digit of our result is 5. 
Result so far: 120469.75
If we take 2150 away from 2200, we end up with 50.
Since there are no more digits in the dividend, we add a zero to the remainder making it 500, and continue the process.

On to step 11:
430 can be fit into 500 1 times, resulting in a remainder of 70.
The number 1 becomes the next digit in our result. 
Result so far: 120469.751
Deduct 430 from 500 and we're left with 70.
Since there are no more digits in the dividend, we add a zero to the remainder making it 700, and continue the process.

Step 12:
430 can be fit into 700 1 times, resulting in a remainder of 270.
Write down 1 as next digit of the result. 
Result so far: 120469.7511
Deduct 430 from 700 and we're left with 270.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2700, and continue the process.

The final outcome is 120469.7511, with a leftover of 0.0027.