We look at the division of 74117817 by 390 
The aim is to understand the frequency of 390 in 74117817.

Advancing to step 1:
390 goes into 7 0 times with a remainder of 7.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we subtract 0 from 7, we get 7.
Take the next digit (4) from the dividend and append it to 7, then repeat: 74 / 390

Moving on to step 2:
If we divide 74 by 390, we get 0 and a remainder of 74.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Deduct 0 from 74 and we're left with 74.
Append the next digit (1) from the dividend to 74 and continue with: 741 / 390

Advancing to step 3:
390 can be fit into 741 1 times, resulting in a remainder of 351.
Write down 1 as next digit of the result. 
Result so far: 1.0
Subtract 390 from 741 to get 351.
Take the next digit (1) from the dividend and append it to 351, then repeat: 3511 / 390

Step 4:
When dividing 3511 by 390, we get 9 with a remainder of 1.
Record the quotient 9 as the next digit in the result. 
Result so far: 19.0
If we subtract 3510 from 3511, we get 1.
Append the next digit (7) from the dividend to 1 and continue with: 17 / 390

Let's proceed to step 5:
390 goes into 17 0 times with a remainder of 17.
Use 0 as the next digit of our solution. 
Result so far: 190.0
The remainder is 17 after subtracting 0 from 17.
Include the next digit (8) from the dividend after 17, then repeat: 178 / 390

Moving on to step 6:
390 goes into 178 0 times with a remainder of 178.
The next digit of our result is 0. 
Result so far: 1900.0
Deduct 0 from 178 and we're left with 178.
Fetch the next digit (1) from the dividend, attach it to 178 and continue: 1781 / 390

Going ahead to step 7:
390 can be fit into 1781 4 times, resulting in a remainder of 221.
The next digit of our result is 4. 
Result so far: 19004.0
Subtract 1560 from 1781 to get 221.
Bring next digit (7) of the dividend behind the 221 and repeat the process: 2217 / 390

On to step 8:
When dividing 2217 by 390, we get 5 with a remainder of 267.
The next digit of our result is 5. 
Result so far: 190045.0
The remainder is 267 after subtracting 1950 from 2217.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2670, and continue the process.

Step 9:
The number 390 fits into 2670 6 times, leaving a remainder of 330.
The number 6 becomes the next digit in our result. 
Result so far: 190045.6
The remainder is 330 after subtracting 2340 from 2670.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3300, and continue the process.

Let's proceed to step 10:
390 goes into 3300 8 times with a remainder of 180.
Record the quotient 8 as the next digit in the result. 
Result so far: 190045.68
The remainder is 180 after subtracting 3120 from 3300.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1800, and continue the process.

Going ahead to step 11:
When dividing 1800 by 390, we get 4 with a remainder of 240.
The number 4 becomes the next digit in our result. 
Result so far: 190045.684
If we subtract 1560 from 1800, we get 240.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2400, and continue the process.

On to step 12:
When dividing 2400 by 390, we get 6 with a remainder of 60.
Put 6 as the next digit of the answer. 
Result so far: 190045.6846
The remainder is 60 after subtracting 2340 from 2400.
Since there are no more digits in the dividend, we add a zero to the remainder making it 600, and continue the process.

Let's proceed to step 13:
The number 390 fits into 600 1 times, leaving a remainder of 210.
Write down 1 as next digit of the result. 
Result so far: 190045.68461
Subtracting 390 from 600 leaves us with 210.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2100, and continue the process.

Advancing to step 14:
When dividing 2100 by 390, we get 5 with a remainder of 150.
The next digit of our result is 5. 
Result so far: 190045.684615
Subtract 1950 from 2100 to get 150.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1500, and continue the process.

On to step 15:
1500 divided by 390 is 3 with a remainder of 330.
The next digit of our result is 3. 
Result so far: 190045.6846153
Deduct 1170 from 1500 and we're left with 330.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3300, and continue the process.

On to step 16:
390 can be fit into 3300 8 times, resulting in a remainder of 180.
The number 8 becomes the next digit in our result. 
Result so far: 190045.68461538
Subtracting 3120 from 3300 leaves us with 180.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1800, and continue the process.

The final result is 190045.68461538 with a remainder of 1.8e-07.