We look at the division of 3951489 by 561 
The aim is to understand the frequency of 561 in 3951489.

Let's proceed to step 1:
561 goes into 3 0 times with a remainder of 3.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtract 0 from 3 to get 3.
Append the next digit (9) from the dividend to 3 and continue with: 39 / 561

Let's proceed to step 2:
561 goes into 39 0 times with a remainder of 39.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we subtract 0 from 39, we get 39.
Fetch the next digit (5) from the dividend, attach it to 39 and continue: 395 / 561

Let's proceed to step 3:
395 divided by 561 is 0 with a remainder of 395.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we take 0 away from 395, we end up with 395.
Append the next digit (1) from the dividend to 395 and continue with: 3951 / 561

Moving on to step 4:
If we divide 3951 by 561, we get 7 and a remainder of 24.
The next digit of our result is 7. 
Result so far: 7.0
Subtract 3927 from 3951 to get 24.
Include the next digit (4) from the dividend after 24, then repeat: 244 / 561

Step 5:
When dividing 244 by 561, we get 0 with a remainder of 244.
Write down 0 as next digit of the result. 
Result so far: 70.0
Subtract 0 from 244 to get 244.
Fetch the next digit (8) from the dividend, attach it to 244 and continue: 2448 / 561

Going ahead to step 6:
2448 divided by 561 is 4 with a remainder of 204.
The next digit of our result is 4. 
Result so far: 704.0
Subtract 2244 from 2448 to get 204.
Take the next digit (9) from the dividend and append it to 204, then repeat: 2049 / 561

On to step 7:
2049 divided by 561 is 3 with a remainder of 366.
Write down 3 as next digit of the result. 
Result so far: 7043.0
Deduct 1683 from 2049 and we're left with 366.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3660, and continue the process.

Advancing to step 8:
561 goes into 3660 6 times with a remainder of 294.
Use 6 as the next digit of our solution. 
Result so far: 7043.6
The remainder is 294 after subtracting 3366 from 3660.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2940, and continue the process.

Moving on to step 9:
The number 561 fits into 2940 5 times, leaving a remainder of 135.
The next digit of our result is 5. 
Result so far: 7043.65
Subtract 2805 from 2940 to get 135.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1350, and continue the process.

Step 10:
The number 561 fits into 1350 2 times, leaving a remainder of 228.
The number 2 becomes the next digit in our result. 
Result so far: 7043.652
Subtract 1122 from 1350 to get 228.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2280, and continue the process.

Let's proceed to step 11:
If we divide 2280 by 561, we get 4 and a remainder of 36.
Record the quotient 4 as the next digit in the result. 
Result so far: 7043.6524
Subtracting 2244 from 2280 leaves us with 36.
Since there are no more digits in the dividend, we add a zero to the remainder making it 360, and continue the process.

Let's proceed to step 12:
If we divide 360 by 561, we get 0 and a remainder of 360.
Put 0 as the next digit of the answer. 
Result so far: 7043.6524
The remainder is 360 after subtracting 0 from 360.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3600, and continue the process.

Step 13:
The number 561 fits into 3600 6 times, leaving a remainder of 234.
Use 6 as the next digit of our solution. 
Result so far: 7043.652406
Deduct 3366 from 3600 and we're left with 234.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2340, and continue the process.

On to step 14:
561 goes into 2340 4 times with a remainder of 96.
Put 4 as the next digit of the answer. 
Result so far: 7043.6524064
Deduct 2244 from 2340 and we're left with 96.
Since there are no more digits in the dividend, we add a zero to the remainder making it 960, and continue the process.

Step 15:
561 can be fit into 960 1 times, resulting in a remainder of 399.
Use 1 as the next digit of our solution. 
Result so far: 7043.65240641
Subtracting 561 from 960 leaves us with 399.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3990, and continue the process.

In conclusion, the division gives 7043.65240641 with a balance of 3.99e-07.