5478520 divided by 390 
The aim is to understand the frequency of 390 in 5478520.

Moving on to step 1:
390 goes into 5 0 times with a remainder of 5.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we subtract 0 from 5, we get 5.
Append the next digit (4) from the dividend to 5 and continue with: 54 / 390

Going ahead to step 2:
390 can be fit into 54 0 times, resulting in a remainder of 54.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we take 0 away from 54, we end up with 54.
Grab the next digit (7) from the dividend, add it to 54, then carry on: 547 / 390

Let's proceed to step 3:
When dividing 547 by 390, we get 1 with a remainder of 157.
Write down 1 as next digit of the result. 
Result so far: 1.0
Deduct 390 from 547 and we're left with 157.
Take the next digit (8) from the dividend and append it to 157, then repeat: 1578 / 390

Advancing to step 4:
390 can be fit into 1578 4 times, resulting in a remainder of 18.
Write down 4 as next digit of the result. 
Result so far: 14.0
Subtract 1560 from 1578 to get 18.
Bring next digit (5) of the dividend behind the 18 and repeat the process: 185 / 390

Step 5:
If we divide 185 by 390, we get 0 and a remainder of 185.
Write down 0 as next digit of the result. 
Result so far: 140.0
The remainder is 185 after subtracting 0 from 185.
Bring next digit (2) of the dividend behind the 185 and repeat the process: 1852 / 390

Step 6:
If we divide 1852 by 390, we get 4 and a remainder of 292.
Use 4 as the next digit of our solution. 
Result so far: 1404.0
If we take 1560 away from 1852, we end up with 292.
Bring next digit (0) of the dividend behind the 292 and repeat the process: 2920 / 390

Going ahead to step 7:
If we divide 2920 by 390, we get 7 and a remainder of 190.
Put 7 as the next digit of the answer. 
Result so far: 14047.0
Deduct 2730 from 2920 and we're left with 190.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1900, and continue the process.

Step 8:
390 goes into 1900 4 times with a remainder of 340.
Use 4 as the next digit of our solution. 
Result so far: 14047.4
Deduct 1560 from 1900 and we're left with 340.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3400, and continue the process.

On to step 9:
The number 390 fits into 3400 8 times, leaving a remainder of 280.
The next digit of our result is 8. 
Result so far: 14047.48
Subtracting 3120 from 3400 leaves us with 280.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2800, and continue the process.

Moving on to step 10:
2800 divided by 390 is 7 with a remainder of 70.
The next digit of our result is 7. 
Result so far: 14047.487
If we subtract 2730 from 2800, we get 70.
Since there are no more digits in the dividend, we add a zero to the remainder making it 700, and continue the process.

Let's proceed to step 11:
When dividing 700 by 390, we get 1 with a remainder of 310.
The next digit of our result is 1. 
Result so far: 14047.4871
If we subtract 390 from 700, we get 310.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3100, and continue the process.

On to step 12:
The number 390 fits into 3100 7 times, leaving a remainder of 370.
Put 7 as the next digit of the answer. 
Result so far: 14047.48717
If we subtract 2730 from 3100, we get 370.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3700, and continue the process.

Let's proceed to step 13:
390 can be fit into 3700 9 times, resulting in a remainder of 190.
The next digit of our result is 9. 
Result so far: 14047.487179
Subtracting 3510 from 3700 leaves us with 190.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1900, and continue the process.

Advancing to step 14:
390 can be fit into 1900 4 times, resulting in a remainder of 340.
Record the quotient 4 as the next digit in the result. 
Result so far: 14047.4871794
If we take 1560 away from 1900, we end up with 340.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3400, and continue the process.

Moving on to step 15:
The number 390 fits into 3400 8 times, leaving a remainder of 280.
The number 8 becomes the next digit in our result. 
Result so far: 14047.48717948
Deduct 3120 from 3400 and we're left with 280.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2800, and continue the process.

The final outcome is 14047.48717948, with a leftover of 2.8e-07.