We're dividing 452400 by 91 
The aim is to understand the frequency of 91 in 452400.

Step 1:
91 can be fit into 4 0 times, resulting in a remainder of 4.
The next digit of our result is 0. 
Result so far: 0.0
Subtract 0 from 4 to get 4.
Grab the next digit (5) from the dividend, add it to 4, then carry on: 45 / 91

Step 2:
91 goes into 45 0 times with a remainder of 45.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
The remainder is 45 after subtracting 0 from 45.
Include the next digit (2) from the dividend after 45, then repeat: 452 / 91

Let's proceed to step 3:
452 divided by 91 is 4 with a remainder of 88.
The number 4 becomes the next digit in our result. 
Result so far: 4.0
If we take 364 away from 452, we end up with 88.
Append the next digit (4) from the dividend to 88 and continue with: 884 / 91

Moving on to step 4:
91 can be fit into 884 9 times, resulting in a remainder of 65.
The number 9 becomes the next digit in our result. 
Result so far: 49.0
The remainder is 65 after subtracting 819 from 884.
Append the next digit (0) from the dividend to 65 and continue with: 650 / 91

Going ahead to step 5:
91 goes into 650 7 times with a remainder of 13.
Record the quotient 7 as the next digit in the result. 
Result so far: 497.0
If we take 637 away from 650, we end up with 13.
Append the next digit (0) from the dividend to 13 and continue with: 130 / 91

Advancing to step 6:
130 divided by 91 is 1 with a remainder of 39.
The next digit of our result is 1. 
Result so far: 4971.0
Deduct 91 from 130 and we're left 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.

Advancing to step 7:
91 can be fit into 390 4 times, resulting in a remainder of 26.
Record the quotient 4 as the next digit in the result. 
Result so far: 4971.4
If we subtract 364 from 390, we get 26.
Since there are no more digits in the dividend, we add a zero to the remainder making it 260, and continue the process.

On to step 8:
91 can be fit into 260 2 times, resulting in a remainder of 78.
Record the quotient 2 as the next digit in the result. 
Result so far: 4971.42
Subtracting 182 from 260 leaves us with 78.
Since there are no more digits in the dividend, we add a zero to the remainder making it 780, and continue the process.

Moving on to step 9:
91 can be fit into 780 8 times, resulting in a remainder of 52.
Record the quotient 8 as the next digit in the result. 
Result so far: 4971.428
Subtracting 728 from 780 leaves us with 52.
Since there are no more digits in the dividend, we add a zero to the remainder making it 520, and continue the process.

Step 10:
The number 91 fits into 520 5 times, leaving a remainder of 65.
Put 5 as the next digit of the answer. 
Result so far: 4971.4285
If we subtract 455 from 520, we get 65.
Since there are no more digits in the dividend, we add a zero to the remainder making it 650, and continue the process.

On to step 11:
The number 91 fits into 650 7 times, leaving a remainder of 13.
Put 7 as the next digit of the answer. 
Result so far: 4971.42857
If we subtract 637 from 650, we get 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 12:
If we divide 130 by 91, we get 1 and a remainder of 39.
The next digit of our result is 1. 
Result so far: 4971.428571
The remainder is 39 after subtracting 91 from 130.
Since there are no more digits in the dividend, we add a zero to the remainder making it 390, and continue the process.

Step 13:
91 can be fit into 390 4 times, resulting in a remainder of 26.
Put 4 as the next digit of the answer. 
Result so far: 4971.4285714
If we take 364 away from 390, we end up with 26.
Since there are no more digits in the dividend, we add a zero to the remainder making it 260, and continue the process.

On to step 14:
91 goes into 260 2 times with a remainder of 78.
Write down 2 as next digit of the result. 
Result so far: 4971.42857142
Deduct 182 from 260 and we're left with 78.
Since there are no more digits in the dividend, we add a zero to the remainder making it 780, and continue the process.

After the division, we end up with 4971.42857142 and a remainder of 7.8e-08.