91440 ÷ 39 
The aim is to understand the frequency of 39 in 91440.

Moving on to step 1:
When dividing 9 by 39, we get 0 with a remainder of 9.
The next digit of our result is 0. 
Result so far: 0.0
Subtracting 0 from 9 leaves us with 9.
Fetch the next digit (1) from the dividend, attach it to 9 and continue: 91 / 39

Let's proceed to step 2:
39 can be fit into 91 2 times, resulting in a remainder of 13.
Put 2 as the next digit of the answer. 
Result so far: 2.0
If we take 78 away from 91, we end up with 13.
Include the next digit (4) from the dividend after 13, then repeat: 134 / 39

Going ahead to step 3:
134 divided by 39 is 3 with a remainder of 17.
Use 3 as the next digit of our solution. 
Result so far: 23.0
The remainder is 17 after subtracting 117 from 134.
Bring next digit (4) of the dividend behind the 17 and repeat the process: 174 / 39

On to step 4:
The number 39 fits into 174 4 times, leaving a remainder of 18.
Record the quotient 4 as the next digit in the result. 
Result so far: 234.0
The remainder is 18 after subtracting 156 from 174.
Fetch the next digit (0) from the dividend, attach it to 18 and continue: 180 / 39

Step 5:
If we divide 180 by 39, we get 4 and a remainder of 24.
Put 4 as the next digit of the answer. 
Result so far: 2344.0
If we take 156 away from 180, we end up with 24.
Since there are no more digits in the dividend, we add a zero to the remainder making it 240, and continue the process.

Going ahead to step 6:
39 can be fit into 240 6 times, resulting in a remainder of 6.
Use 6 as the next digit of our solution. 
Result so far: 2344.6
If we subtract 234 from 240, we get 6.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

Going ahead to step 7:
39 can be fit into 60 1 times, resulting in a remainder of 21.
Use 1 as the next digit of our solution. 
Result so far: 2344.61
Subtract 39 from 60 to get 21.
Since there are no more digits in the dividend, we add a zero to the remainder making it 210, and continue the process.

Step 8:
39 goes into 210 5 times with a remainder of 15.
Record the quotient 5 as the next digit in the result. 
Result so far: 2344.615
Subtract 195 from 210 to get 15.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

On to step 9:
150 divided by 39 is 3 with a remainder of 33.
Put 3 as the next digit of the answer. 
Result so far: 2344.6153
The remainder is 33 after subtracting 117 from 150.
Since there are no more digits in the dividend, we add a zero to the remainder making it 330, and continue the process.

Going ahead to step 10:
If we divide 330 by 39, we get 8 and a remainder of 18.
Record the quotient 8 as the next digit in the result. 
Result so far: 2344.61538
Deduct 312 from 330 and we're left with 18.
Since there are no more digits in the dividend, we add a zero to the remainder making it 180, and continue the process.

Advancing to step 11:
The number 39 fits into 180 4 times, leaving a remainder of 24.
Record the quotient 4 as the next digit in the result. 
Result so far: 2344.615384
If we subtract 156 from 180, we get 24.
Since there are no more digits in the dividend, we add a zero to the remainder making it 240, and continue the process.

Advancing to step 12:
240 divided by 39 is 6 with a remainder of 6.
The number 6 becomes the next digit in our result. 
Result so far: 2344.6153846
Subtracting 234 from 240 leaves us with 6.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

Going ahead to step 13:
The number 39 fits into 60 1 times, leaving a remainder of 21.
Write down 1 as next digit of the result. 
Result so far: 2344.61538461
The remainder is 21 after subtracting 39 from 60.
Since there are no more digits in the dividend, we add a zero to the remainder making it 210, and continue the process.

The final result is 2344.61538461 with a remainder of 2.1e-08.