Let's divide 44510574 by 399
The aim is to understand the frequency of 399 in 44510574.

On to step 1:
4 divided by 399 is 0 with a remainder of 4.
Put 0 as the next digit of the answer. 
Result so far: 0.0
If we take 0 away from 4, we end up with 4.
Bring next digit (4) of the dividend behind the 4 and repeat the process: 44 / 399

Moving on to step 2:
The number 399 fits into 44 0 times, leaving a remainder of 44.
The next digit of our result is 0. 
Result so far: 0.0
The remainder is 44 after subtracting 0 from 44.
Include the next digit (5) from the dividend after 44, then repeat: 445 / 399

Moving on to step 3:
If we divide 445 by 399, we get 1 and a remainder of 46.
Use 1 as the next digit of our solution. 
Result so far: 1.0
Deduct 399 from 445 and we're left with 46.
Fetch the next digit (1) from the dividend, attach it to 46 and continue: 461 / 399

Step 4:
If we divide 461 by 399, we get 1 and a remainder of 62.
Use 1 as the next digit of our solution. 
Result so far: 11.0
Deduct 399 from 461 and we're left with 62.
Include the next digit (0) from the dividend after 62, then repeat: 620 / 399

On to step 5:
If we divide 620 by 399, we get 1 and a remainder of 221.
The next digit of our result is 1. 
Result so far: 111.0
If we take 399 away from 620, we end up with 221.
Grab the next digit (5) from the dividend, add it to 221, then carry on: 2215 / 399

Let's proceed to step 6:
399 goes into 2215 5 times with a remainder of 220.
Put 5 as the next digit of the answer. 
Result so far: 1115.0
If we take 1995 away from 2215, we end up with 220.
Take the next digit (7) from the dividend and append it to 220, then repeat: 2207 / 399

Moving on to step 7:
If we divide 2207 by 399, we get 5 and a remainder of 212.
Put 5 as the next digit of the answer. 
Result so far: 11155.0
The remainder is 212 after subtracting 1995 from 2207.
Append the next digit (4) from the dividend to 212 and continue with: 2124 / 399

Advancing to step 8:
If we divide 2124 by 399, we get 5 and a remainder of 129.
The number 5 becomes the next digit in our result. 
Result so far: 111555.0
The remainder is 129 after subtracting 1995 from 2124.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1290, and continue the process.

Advancing to step 9:
When dividing 1290 by 399, we get 3 with a remainder of 93.
The number 3 becomes the next digit in our result. 
Result so far: 111555.3
If we take 1197 away from 1290, we end up with 93.
Since there are no more digits in the dividend, we add a zero to the remainder making it 930, and continue the process.

Let's proceed to step 10:
399 goes into 930 2 times with a remainder of 132.
Use 2 as the next digit of our solution. 
Result so far: 111555.32
Subtract 798 from 930 to get 132.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1320, and continue the process.

Advancing to step 11:
The number 399 fits into 1320 3 times, leaving a remainder of 123.
Write down 3 as next digit of the result. 
Result so far: 111555.323
The remainder is 123 after subtracting 1197 from 1320.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1230, and continue the process.

Step 12:
If we divide 1230 by 399, we get 3 and a remainder of 33.
Record the quotient 3 as the next digit in the result. 
Result so far: 111555.3233
If we take 1197 away from 1230, we end up with 33.
Since there are no more digits in the dividend, we add a zero to the remainder making it 330, and continue the process.

After the division, we end up with 111555.3233 and a remainder of 0.00033.