We're dividing 43001989 by 558 
The aim is to understand the frequency of 558 in 43001989.

Let's proceed to step 1:
The number 558 fits into 4 0 times, leaving a remainder of 4.
Use 0 as the next digit of our solution. 
Result so far: 0.0
The remainder is 4 after subtracting 0 from 4.
Include the next digit (3) from the dividend after 4, then repeat: 43 / 558

Step 2:
When dividing 43 by 558, we get 0 with a remainder of 43.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Deduct 0 from 43 and we're left with 43.
Take the next digit (0) from the dividend and append it to 43, then repeat: 430 / 558

Step 3:
When dividing 430 by 558, we get 0 with a remainder of 430.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 430 to get 430.
Bring next digit (0) of the dividend behind the 430 and repeat the process: 4300 / 558

Moving on to step 4:
4300 divided by 558 is 7 with a remainder of 394.
Write down 7 as next digit of the result. 
Result so far: 7.0
Subtract 3906 from 4300 to get 394.
Bring next digit (1) of the dividend behind the 394 and repeat the process: 3941 / 558

Step 5:
558 can be fit into 3941 7 times, resulting in a remainder of 35.
Put 7 as the next digit of the answer. 
Result so far: 77.0
If we take 3906 away from 3941, we end up with 35.
Include the next digit (9) from the dividend after 35, then repeat: 359 / 558

Advancing to step 6:
359 divided by 558 is 0 with a remainder of 359.
Record the quotient 0 as the next digit in the result. 
Result so far: 770.0
The remainder is 359 after subtracting 0 from 359.
Grab the next digit (8) from the dividend, add it to 359, then carry on: 3598 / 558

On to step 7:
558 can be fit into 3598 6 times, resulting in a remainder of 250.
Record the quotient 6 as the next digit in the result. 
Result so far: 7706.0
Subtracting 3348 from 3598 leaves us with 250.
Fetch the next digit (9) from the dividend, attach it to 250 and continue: 2509 / 558

Let's proceed to step 8:
558 goes into 2509 4 times with a remainder of 277.
Write down 4 as next digit of the result. 
Result so far: 77064.0
If we subtract 2232 from 2509, we get 277.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2770, and continue the process.

Let's proceed to step 9:
If we divide 2770 by 558, we get 4 and a remainder of 538.
Put 4 as the next digit of the answer. 
Result so far: 77064.4
Subtract 2232 from 2770 to get 538.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5380, and continue the process.

Moving on to step 10:
The number 558 fits into 5380 9 times, leaving a remainder of 358.
Put 9 as the next digit of the answer. 
Result so far: 77064.49
Subtracting 5022 from 5380 leaves us with 358.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3580, and continue the process.

On to step 11:
3580 divided by 558 is 6 with a remainder of 232.
The next digit of our result is 6. 
Result so far: 77064.496
If we subtract 3348 from 3580, we get 232.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2320, and continue the process.

Moving on to step 12:
The number 558 fits into 2320 4 times, leaving a remainder of 88.
Put 4 as the next digit of the answer. 
Result so far: 77064.4964
Deduct 2232 from 2320 and we're left with 88.
Since there are no more digits in the dividend, we add a zero to the remainder making it 880, and continue the process.

Moving on to step 13:
558 can be fit into 880 1 times, resulting in a remainder of 322.
The number 1 becomes the next digit in our result. 
Result so far: 77064.49641
If we take 558 away from 880, we end up with 322.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3220, and continue the process.

Step 14:
3220 divided by 558 is 5 with a remainder of 430.
Record the quotient 5 as the next digit in the result. 
Result so far: 77064.496415
If we take 2790 away from 3220, we end up with 430.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4300, and continue the process.

Advancing to step 15:
The number 558 fits into 4300 7 times, leaving a remainder of 394.
Record the quotient 7 as the next digit in the result. 
Result so far: 77064.4964157
The remainder is 394 after subtracting 3906 from 4300.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3940, and continue the process.

Step 16:
When dividing 3940 by 558, we get 7 with a remainder of 34.
The next digit of our result is 7. 
Result so far: 77064.49641577
The remainder is 34 after subtracting 3906 from 3940.
Since there are no more digits in the dividend, we add a zero to the remainder making it 340, and continue the process.

The final outcome is 77064.49641577, with a leftover of 3.4e-08.