We're dividing 8421476 by 390 
The aim is to understand the frequency of 390 in 8421476.

Let's proceed to step 1:
The number 390 fits into 8 0 times, leaving a remainder of 8.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Deduct 0 from 8 and we're left with 8.
Grab the next digit (4) from the dividend, add it to 8, then carry on: 84 / 390

Moving on to step 2:
The number 390 fits into 84 0 times, leaving a remainder of 84.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Deduct 0 from 84 and we're left with 84.
Fetch the next digit (2) from the dividend, attach it to 84 and continue: 842 / 390

Advancing to step 3:
390 goes into 842 2 times with a remainder of 62.
Write down 2 as next digit of the result. 
Result so far: 2.0
If we subtract 780 from 842, we get 62.
Include the next digit (1) from the dividend after 62, then repeat: 621 / 390

Going ahead to step 4:
390 goes into 621 1 times with a remainder of 231.
Record the quotient 1 as the next digit in the result. 
Result so far: 21.0
The remainder is 231 after subtracting 390 from 621.
Fetch the next digit (4) from the dividend, attach it to 231 and continue: 2314 / 390

Advancing to step 5:
390 can be fit into 2314 5 times, resulting in a remainder of 364.
The next digit of our result is 5. 
Result so far: 215.0
Deduct 1950 from 2314 and we're left with 364.
Bring next digit (7) of the dividend behind the 364 and repeat the process: 3647 / 390

Moving on to step 6:
When dividing 3647 by 390, we get 9 with a remainder of 137.
The number 9 becomes the next digit in our result. 
Result so far: 2159.0
If we subtract 3510 from 3647, we get 137.
Fetch the next digit (6) from the dividend, attach it to 137 and continue: 1376 / 390

Let's proceed to step 7:
390 goes into 1376 3 times with a remainder of 206.
Use 3 as the next digit of our solution. 
Result so far: 21593.0
If we subtract 1170 from 1376, we get 206.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2060, and continue the process.

Step 8:
390 can be fit into 2060 5 times, resulting in a remainder of 110.
Put 5 as the next digit of the answer. 
Result so far: 21593.5
If we take 1950 away from 2060, we end up with 110.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1100, and continue the process.

Going ahead to step 9:
1100 divided by 390 is 2 with a remainder of 320.
Record the quotient 2 as the next digit in the result. 
Result so far: 21593.52
The remainder is 320 after subtracting 780 from 1100.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3200, and continue the process.

On to step 10:
390 can be fit into 3200 8 times, resulting in a remainder of 80.
Use 8 as the next digit of our solution. 
Result so far: 21593.528
The remainder is 80 after subtracting 3120 from 3200.
Since there are no more digits in the dividend, we add a zero to the remainder making it 800, and continue the process.

Let's proceed to step 11:
The number 390 fits into 800 2 times, leaving a remainder of 20.
Record the quotient 2 as the next digit in the result. 
Result so far: 21593.5282
If we take 780 away from 800, we end up with 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Step 12:
When dividing 200 by 390, we get 0 with a remainder of 200.
Use 0 as the next digit of our solution. 
Result so far: 21593.5282
If we take 0 away from 200, we end up with 200.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2000, and continue the process.

Step 13:
2000 divided by 390 is 5 with a remainder of 50.
The number 5 becomes the next digit in our result. 
Result so far: 21593.528205
Deduct 1950 from 2000 and we're left with 50.
Since there are no more digits in the dividend, we add a zero to the remainder making it 500, and continue the process.

Step 14:
500 divided by 390 is 1 with a remainder of 110.
Write down 1 as next digit of the result. 
Result so far: 21593.5282051
Subtract 390 from 500 to get 110.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1100, and continue the process.

Moving on to step 15:
If we divide 1100 by 390, we get 2 and a remainder of 320.
The next digit of our result is 2. 
Result so far: 21593.52820512
Subtract 780 from 1100 to get 320.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3200, and continue the process.

After the division, we end up with 21593.52820512 and a remainder of 3.2e-07.