81507004 ÷ 423 
The aim is to understand the frequency of 423 in 81507004.

On to step 1:
If we divide 8 by 423, we get 0 and a remainder of 8.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Deduct 0 from 8 and we're left with 8.
Take the next digit (1) from the dividend and append it to 8, then repeat: 81 / 423

Let's proceed to step 2:
81 divided by 423 is 0 with a remainder of 81.
The next digit of our result is 0. 
Result so far: 0.0
Subtracting 0 from 81 leaves us with 81.
Bring next digit (5) of the dividend behind the 81 and repeat the process: 815 / 423

Advancing to step 3:
The number 423 fits into 815 1 times, leaving a remainder of 392.
Write down 1 as next digit of the result. 
Result so far: 1.0
The remainder is 392 after subtracting 423 from 815.
Append the next digit (0) from the dividend to 392 and continue with: 3920 / 423

On to step 4:
The number 423 fits into 3920 9 times, leaving a remainder of 113.
The number 9 becomes the next digit in our result. 
Result so far: 19.0
If we subtract 3807 from 3920, we get 113.
Grab the next digit (7) from the dividend, add it to 113, then carry on: 1137 / 423

Advancing to step 5:
When dividing 1137 by 423, we get 2 with a remainder of 291.
Put 2 as the next digit of the answer. 
Result so far: 192.0
Subtracting 846 from 1137 leaves us with 291.
Bring next digit (0) of the dividend behind the 291 and repeat the process: 2910 / 423

Advancing to step 6:
The number 423 fits into 2910 6 times, leaving a remainder of 372.
Put 6 as the next digit of the answer. 
Result so far: 1926.0
Deduct 2538 from 2910 and we're left with 372.
Fetch the next digit (0) from the dividend, attach it to 372 and continue: 3720 / 423

Step 7:
The number 423 fits into 3720 8 times, leaving a remainder of 336.
The number 8 becomes the next digit in our result. 
Result so far: 19268.0
If we take 3384 away from 3720, we end up with 336.
Grab the next digit (4) from the dividend, add it to 336, then carry on: 3364 / 423

Step 8:
3364 divided by 423 is 7 with a remainder of 403.
The number 7 becomes the next digit in our result. 
Result so far: 192687.0
Subtract 2961 from 3364 to get 403.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4030, and continue the process.

On to step 9:
423 can be fit into 4030 9 times, resulting in a remainder of 223.
Record the quotient 9 as the next digit in the result. 
Result so far: 192687.9
If we take 3807 away from 4030, we end up with 223.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2230, and continue the process.

Moving on to step 10:
The number 423 fits into 2230 5 times, leaving a remainder of 115.
The number 5 becomes the next digit in our result. 
Result so far: 192687.95
Subtracting 2115 from 2230 leaves us with 115.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1150, and continue the process.

Advancing to step 11:
The number 423 fits into 1150 2 times, leaving a remainder of 304.
The next digit of our result is 2. 
Result so far: 192687.952
The remainder is 304 after subtracting 846 from 1150.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3040, and continue the process.

Let's proceed to step 12:
If we divide 3040 by 423, we get 7 and a remainder of 79.
The number 7 becomes the next digit in our result. 
Result so far: 192687.9527
If we subtract 2961 from 3040, we get 79.
Since there are no more digits in the dividend, we add a zero to the remainder making it 790, and continue the process.

On to step 13:
790 divided by 423 is 1 with a remainder of 367.
Record the quotient 1 as the next digit in the result. 
Result so far: 192687.95271
Deduct 423 from 790 and we're left with 367.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3670, and continue the process.

Step 14:
423 goes into 3670 8 times with a remainder of 286.
Record the quotient 8 as the next digit in the result. 
Result so far: 192687.952718
The remainder is 286 after subtracting 3384 from 3670.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2860, and continue the process.

Going ahead to step 15:
When dividing 2860 by 423, we get 6 with a remainder of 322.
The next digit of our result is 6. 
Result so far: 192687.9527186
Subtracting 2538 from 2860 leaves us with 322.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3220, and continue the process.

Let's proceed to step 16:
The number 423 fits into 3220 7 times, leaving a remainder of 259.
Put 7 as the next digit of the answer. 
Result so far: 192687.95271867
The remainder is 259 after subtracting 2961 from 3220.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2590, and continue the process.

Our division results in 192687.95271867 with a remaining 2.59e-07.