121951 divided by 39 
The aim is to understand the frequency of 39 in 121951.

Let's proceed to step 1:
1 divided by 39 is 0 with a remainder of 1.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we subtract 0 from 1, we get 1.
Grab the next digit (2) from the dividend, add it to 1, then carry on: 12 / 39

Going ahead to step 2:
39 can be fit into 12 0 times, resulting in a remainder of 12.
The next digit of our result is 0. 
Result so far: 0.0
Subtract 0 from 12 to get 12.
Fetch the next digit (1) from the dividend, attach it to 12 and continue: 121 / 39

Let's proceed to step 3:
When dividing 121 by 39, we get 3 with a remainder of 4.
The next digit of our result is 3. 
Result so far: 3.0
Subtracting 117 from 121 leaves us with 4.
Include the next digit (9) from the dividend after 4, then repeat: 49 / 39

On to step 4:
39 goes into 49 1 times with a remainder of 10.
Write down 1 as next digit of the result. 
Result so far: 31.0
If we subtract 39 from 49, we get 10.
Fetch the next digit (5) from the dividend, attach it to 10 and continue: 105 / 39

On to step 5:
When dividing 105 by 39, we get 2 with a remainder of 27.
Put 2 as the next digit of the answer. 
Result so far: 312.0
Subtracting 78 from 105 leaves us with 27.
Bring next digit (1) of the dividend behind the 27 and repeat the process: 271 / 39

Let's proceed to step 6:
If we divide 271 by 39, we get 6 and a remainder of 37.
The next digit of our result is 6. 
Result so far: 3126.0
Subtract 234 from 271 to get 37.
Since there are no more digits in the dividend, we add a zero to the remainder making it 370, and continue the process.

Going ahead to step 7:
If we divide 370 by 39, we get 9 and a remainder of 19.
Record the quotient 9 as the next digit in the result. 
Result so far: 3126.9
Subtract 351 from 370 to get 19.
Since there are no more digits in the dividend, we add a zero to the remainder making it 190, and continue the process.

On to step 8:
39 goes into 190 4 times with a remainder of 34.
The next digit of our result is 4. 
Result so far: 3126.94
If we subtract 156 from 190, we get 34.
Since there are no more digits in the dividend, we add a zero to the remainder making it 340, and continue the process.

Moving on to step 9:
340 divided by 39 is 8 with a remainder of 28.
Put 8 as the next digit of the answer. 
Result so far: 3126.948
Subtracting 312 from 340 leaves us with 28.
Since there are no more digits in the dividend, we add a zero to the remainder making it 280, and continue the process.

On to step 10:
If we divide 280 by 39, we get 7 and a remainder of 7.
Record the quotient 7 as the next digit in the result. 
Result so far: 3126.9487
If we take 273 away from 280, we end up with 7.
Since there are no more digits in the dividend, we add a zero to the remainder making it 70, and continue the process.

Going ahead to step 11:
39 can be fit into 70 1 times, resulting in a remainder of 31.
Write down 1 as next digit of the result. 
Result so far: 3126.94871
Subtract 39 from 70 to get 31.
Since there are no more digits in the dividend, we add a zero to the remainder making it 310, and continue the process.

Going ahead to step 12:
The number 39 fits into 310 7 times, leaving a remainder of 37.
Write down 7 as next digit of the result. 
Result so far: 3126.948717
Subtract 273 from 310 to get 37.
Since there are no more digits in the dividend, we add a zero to the remainder making it 370, and continue the process.

Step 13:
When dividing 370 by 39, we get 9 with a remainder of 19.
Put 9 as the next digit of the answer. 
Result so far: 3126.9487179
Subtracting 351 from 370 leaves us with 19.
Since there are no more digits in the dividend, we add a zero to the remainder making it 190, and continue the process.

Going ahead to step 14:
190 divided by 39 is 4 with a remainder of 34.
Record the quotient 4 as the next digit in the result. 
Result so far: 3126.94871794
The remainder is 34 after subtracting 156 from 190.
Since there are no more digits in the dividend, we add a zero to the remainder making it 340, and continue the process.

After the division, we end up with 3126.94871794 and a remainder of 3.4e-08.