We look at the division of 34207143 by 991 
The aim is to understand the frequency of 991 in 34207143.

Advancing to step 1:
3 divided by 991 is 0 with a remainder of 3.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtracting 0 from 3 leaves us with 3.
Fetch the next digit (4) from the dividend, attach it to 3 and continue: 34 / 991

On to step 2:
When dividing 34 by 991, we get 0 with a remainder of 34.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Deduct 0 from 34 and we're left with 34.
Append the next digit (2) from the dividend to 34 and continue with: 342 / 991

Advancing to step 3:
The number 991 fits into 342 0 times, leaving a remainder of 342.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtracting 0 from 342 leaves us with 342.
Append the next digit (0) from the dividend to 342 and continue with: 3420 / 991

On to step 4:
991 goes into 3420 3 times with a remainder of 447.
The number 3 becomes the next digit in our result. 
Result so far: 3.0
Subtract 2973 from 3420 to get 447.
Bring next digit (7) of the dividend behind the 447 and repeat the process: 4477 / 991

Going ahead to step 5:
The number 991 fits into 4477 4 times, leaving a remainder of 513.
Put 4 as the next digit of the answer. 
Result so far: 34.0
Subtracting 3964 from 4477 leaves us with 513.
Include the next digit (1) from the dividend after 513, then repeat: 5131 / 991

Moving on to step 6:
991 can be fit into 5131 5 times, resulting in a remainder of 176.
Put 5 as the next digit of the answer. 
Result so far: 345.0
Subtract 4955 from 5131 to get 176.
Bring next digit (4) of the dividend behind the 176 and repeat the process: 1764 / 991

Let's proceed to step 7:
1764 divided by 991 is 1 with a remainder of 773.
Write down 1 as next digit of the result. 
Result so far: 3451.0
Subtracting 991 from 1764 leaves us with 773.
Grab the next digit (3) from the dividend, add it to 773, then carry on: 7733 / 991

Advancing to step 8:
When dividing 7733 by 991, we get 7 with a remainder of 796.
The next digit of our result is 7. 
Result so far: 34517.0
If we take 6937 away from 7733, we end up with 796.
Since there are no more digits in the dividend, we add a zero to the remainder making it 7960, and continue the process.

On to step 9:
If we divide 7960 by 991, we get 8 and a remainder of 32.
The next digit of our result is 8. 
Result so far: 34517.8
The remainder is 32 after subtracting 7928 from 7960.
Since there are no more digits in the dividend, we add a zero to the remainder making it 320, and continue the process.

On to step 10:
The number 991 fits into 320 0 times, leaving a remainder of 320.
Record the quotient 0 as the next digit in the result. 
Result so far: 34517.8
The remainder is 320 after subtracting 0 from 320.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3200, and continue the process.

Going ahead to step 11:
If we divide 3200 by 991, we get 3 and a remainder of 227.
Write down 3 as next digit of the result. 
Result so far: 34517.803
The remainder is 227 after subtracting 2973 from 3200.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2270, and continue the process.

On to step 12:
2270 divided by 991 is 2 with a remainder of 288.
The next digit of our result is 2. 
Result so far: 34517.8032
If we take 1982 away from 2270, we end up with 288.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2880, and continue the process.

Moving on to step 13:
991 can be fit into 2880 2 times, resulting in a remainder of 898.
Record the quotient 2 as the next digit in the result. 
Result so far: 34517.80322
Subtract 1982 from 2880 to get 898.
Since there are no more digits in the dividend, we add a zero to the remainder making it 8980, and continue the process.

The final outcome is 34517.80322, with a leftover of 0.000898.