We look at the division of 91518019 by 71 
The aim is to understand the frequency of 71 in 91518019.

Advancing to step 1:
71 can be fit into 9 0 times, resulting in a remainder of 9.
The next digit of our result is 0. 
Result so far: 0.0
If we subtract 0 from 9, we get 9.
Include the next digit (1) from the dividend after 9, then repeat: 91 / 71

Advancing to step 2:
The number 71 fits into 91 1 times, leaving a remainder of 20.
The next digit of our result is 1. 
Result so far: 1.0
Subtracting 71 from 91 leaves us with 20.
Fetch the next digit (5) from the dividend, attach it to 20 and continue: 205 / 71

Step 3:
If we divide 205 by 71, we get 2 and a remainder of 63.
Record the quotient 2 as the next digit in the result. 
Result so far: 12.0
Subtracting 142 from 205 leaves us with 63.
Grab the next digit (1) from the dividend, add it to 63, then carry on: 631 / 71

On to step 4:
631 divided by 71 is 8 with a remainder of 63.
Use 8 as the next digit of our solution. 
Result so far: 128.0
The remainder is 63 after subtracting 568 from 631.
Include the next digit (8) from the dividend after 63, then repeat: 638 / 71

Step 5:
The number 71 fits into 638 8 times, leaving a remainder of 70.
Write down 8 as next digit of the result. 
Result so far: 1288.0
Deduct 568 from 638 and we're left with 70.
Append the next digit (0) from the dividend to 70 and continue with: 700 / 71

Let's proceed to step 6:
When dividing 700 by 71, we get 9 with a remainder of 61.
Put 9 as the next digit of the answer. 
Result so far: 12889.0
If we take 639 away from 700, we end up with 61.
Include the next digit (1) from the dividend after 61, then repeat: 611 / 71

Going ahead to step 7:
If we divide 611 by 71, we get 8 and a remainder of 43.
The next digit of our result is 8. 
Result so far: 128898.0
Deduct 568 from 611 and we're left with 43.
Take the next digit (9) from the dividend and append it to 43, then repeat: 439 / 71

Going ahead to step 8:
When dividing 439 by 71, we get 6 with a remainder of 13.
Record the quotient 6 as the next digit in the result. 
Result so far: 1288986.0
Deduct 426 from 439 and we're left with 13.
Since there are no more digits in the dividend, we add a zero to the remainder making it 130, and continue the process.

Step 9:
71 goes into 130 1 times with a remainder of 59.
The next digit of our result is 1. 
Result so far: 1288986.1
If we subtract 71 from 130, we get 59.
Since there are no more digits in the dividend, we add a zero to the remainder making it 590, and continue the process.

Advancing to step 10:
71 can be fit into 590 8 times, resulting in a remainder of 22.
The next digit of our result is 8. 
Result so far: 1288986.18
If we subtract 568 from 590, we get 22.
Since there are no more digits in the dividend, we add a zero to the remainder making it 220, and continue the process.

Moving on to step 11:
The number 71 fits into 220 3 times, leaving a remainder of 7.
Put 3 as the next digit of the answer. 
Result so far: 1288986.183
Subtract 213 from 220 to get 7.
Since there are no more digits in the dividend, we add a zero to the remainder making it 70, and continue the process.

Let's proceed to step 12:
71 goes into 70 0 times with a remainder of 70.
The number 0 becomes the next digit in our result. 
Result so far: 1288986.183
If we take 0 away from 70, we end up 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.

On to step 13:
The number 71 fits into 700 9 times, leaving a remainder of 61.
Put 9 as the next digit of the answer. 
Result so far: 1288986.18309
The remainder is 61 after subtracting 639 from 700.
Since there are no more digits in the dividend, we add a zero to the remainder making it 610, and continue the process.

Let's proceed to step 14:
If we divide 610 by 71, we get 8 and a remainder of 42.
Put 8 as the next digit of the answer. 
Result so far: 1288986.183098
Subtracting 568 from 610 leaves us with 42.
Since there are no more digits in the dividend, we add a zero to the remainder making it 420, and continue the process.

Step 15:
If we divide 420 by 71, we get 5 and a remainder of 65.
Write down 5 as next digit of the result. 
Result so far: 1288986.1830985
Subtracting 355 from 420 leaves us with 65.
Since there are no more digits in the dividend, we add a zero to the remainder making it 650, and continue the process.

Advancing to step 16:
650 divided by 71 is 9 with a remainder of 11.
Use 9 as the next digit of our solution. 
Result so far: 1288986.18309859
If we subtract 639 from 650, we get 11.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

In conclusion, the division gives 1288986.18309859 with a balance of 1.1e-08.