We look at the division of 51643153 by 129 
The aim is to understand the frequency of 129 in 51643153.

Going ahead to step 1:
When dividing 5 by 129, we get 0 with a remainder of 5.
The next digit of our result is 0. 
Result so far: 0.0
Deduct 0 from 5 and we're left with 5.
Bring next digit (1) of the dividend behind the 5 and repeat the process: 51 / 129

Advancing to step 2:
129 can be fit into 51 0 times, resulting in a remainder of 51.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtracting 0 from 51 leaves us with 51.
Grab the next digit (6) from the dividend, add it to 51, then carry on: 516 / 129

Moving on to step 3:
When dividing 516 by 129, we get 4 with a remainder of 0.
The number 4 becomes the next digit in our result. 
Result so far: 4.0
Subtracting 516 from 516 leaves us with 0.
Bring next digit (4) of the dividend behind the 0 and repeat the process: 4 / 129

Step 4:
The number 129 fits into 4 0 times, leaving a remainder of 4.
Use 0 as the next digit of our solution. 
Result so far: 40.0
Subtracting 0 from 4 leaves us with 4.
Append the next digit (3) from the dividend to 4 and continue with: 43 / 129

Moving on to step 5:
129 can be fit into 43 0 times, resulting in a remainder of 43.
The number 0 becomes the next digit in our result. 
Result so far: 400.0
If we take 0 away from 43, we end up with 43.
Grab the next digit (1) from the dividend, add it to 43, then carry on: 431 / 129

On to step 6:
129 goes into 431 3 times with a remainder of 44.
Record the quotient 3 as the next digit in the result. 
Result so far: 4003.0
If we subtract 387 from 431, we get 44.
Bring next digit (5) of the dividend behind the 44 and repeat the process: 445 / 129

Let's proceed to step 7:
129 can be fit into 445 3 times, resulting in a remainder of 58.
The number 3 becomes the next digit in our result. 
Result so far: 40033.0
If we take 387 away from 445, we end up with 58.
Fetch the next digit (3) from the dividend, attach it to 58 and continue: 583 / 129

On to step 8:
When dividing 583 by 129, we get 4 with a remainder of 67.
Record the quotient 4 as the next digit in the result. 
Result so far: 400334.0
If we subtract 516 from 583, we get 67.
Since there are no more digits in the dividend, we add a zero to the remainder making it 670, and continue the process.

On to step 9:
129 goes into 670 5 times with a remainder of 25.
Put 5 as the next digit of the answer. 
Result so far: 400334.5
Deduct 645 from 670 and we're left with 25.
Since there are no more digits in the dividend, we add a zero to the remainder making it 250, and continue the process.

Step 10:
If we divide 250 by 129, we get 1 and a remainder of 121.
Use 1 as the next digit of our solution. 
Result so far: 400334.51
If we take 129 away from 250, we end up with 121.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1210, and continue the process.

Going ahead to step 11:
The number 129 fits into 1210 9 times, leaving a remainder of 49.
The next digit of our result is 9. 
Result so far: 400334.519
Deduct 1161 from 1210 and we're left with 49.
Since there are no more digits in the dividend, we add a zero to the remainder making it 490, and continue the process.

Let's proceed to step 12:
When dividing 490 by 129, we get 3 with a remainder of 103.
Put 3 as the next digit of the answer. 
Result so far: 400334.5193
If we take 387 away from 490, we end up with 103.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1030, and continue the process.

Going ahead to step 13:
If we divide 1030 by 129, we get 7 and a remainder of 127.
The next digit of our result is 7. 
Result so far: 400334.51937
If we take 903 away from 1030, we end up with 127.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1270, and continue the process.

Moving on to step 14:
The number 129 fits into 1270 9 times, leaving a remainder of 109.
Put 9 as the next digit of the answer. 
Result so far: 400334.519379
The remainder is 109 after subtracting 1161 from 1270.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1090, and continue the process.

On to step 15:
When dividing 1090 by 129, we get 8 with a remainder of 58.
Put 8 as the next digit of the answer. 
Result so far: 400334.5193798
If we subtract 1032 from 1090, we get 58.
Since there are no more digits in the dividend, we add a zero to the remainder making it 580, and continue the process.

Let's proceed to step 16:
The number 129 fits into 580 4 times, leaving a remainder of 64.
Write down 4 as next digit of the result. 
Result so far: 400334.51937984
Subtract 516 from 580 to get 64.
Since there are no more digits in the dividend, we add a zero to the remainder making it 640, and continue the process.

Our division results in 400334.51937984 with a remaining 6.4e-08.