Let's divide 42603587 by 558
The aim is to understand the frequency of 558 in 42603587.

On to step 1:
558 goes into 4 0 times with a remainder of 4.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Deduct 0 from 4 and we're left with 4.
Bring next digit (2) of the dividend behind the 4 and repeat the process: 42 / 558

Advancing to step 2:
When dividing 42 by 558, we get 0 with a remainder of 42.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Deduct 0 from 42 and we're left with 42.
Bring next digit (6) of the dividend behind the 42 and repeat the process: 426 / 558

Going ahead to step 3:
426 divided by 558 is 0 with a remainder of 426.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Deduct 0 from 426 and we're left with 426.
Include the next digit (0) from the dividend after 426, then repeat: 4260 / 558

Moving on to step 4:
When dividing 4260 by 558, we get 7 with a remainder of 354.
The number 7 becomes the next digit in our result. 
Result so far: 7.0
Subtracting 3906 from 4260 leaves us with 354.
Fetch the next digit (3) from the dividend, attach it to 354 and continue: 3543 / 558

Going ahead to step 5:
3543 divided by 558 is 6 with a remainder of 195.
Put 6 as the next digit of the answer. 
Result so far: 76.0
Deduct 3348 from 3543 and we're left with 195.
Take the next digit (5) from the dividend and append it to 195, then repeat: 1955 / 558

Step 6:
When dividing 1955 by 558, we get 3 with a remainder of 281.
Write down 3 as next digit of the result. 
Result so far: 763.0
Subtracting 1674 from 1955 leaves us with 281.
Fetch the next digit (8) from the dividend, attach it to 281 and continue: 2818 / 558

On to step 7:
2818 divided by 558 is 5 with a remainder of 28.
Write down 5 as next digit of the result. 
Result so far: 7635.0
If we take 2790 away from 2818, we end up with 28.
Append the next digit (7) from the dividend to 28 and continue with: 287 / 558

Step 8:
558 can be fit into 287 0 times, resulting in a remainder of 287.
Put 0 as the next digit of the answer. 
Result so far: 76350.0
If we take 0 away from 287, we end up with 287.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2870, and continue the process.

On to step 9:
When dividing 2870 by 558, we get 5 with a remainder of 80.
Write down 5 as next digit of the result. 
Result so far: 76350.5
Deduct 2790 from 2870 and we're left with 80.
Since there are no more digits in the dividend, we add a zero to the remainder making it 800, and continue the process.

Step 10:
The number 558 fits into 800 1 times, leaving a remainder of 242.
Write down 1 as next digit of the result. 
Result so far: 76350.51
If we take 558 away from 800, we end up with 242.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2420, and continue the process.

Step 11:
558 can be fit into 2420 4 times, resulting in a remainder of 188.
Write down 4 as next digit of the result. 
Result so far: 76350.514
Subtract 2232 from 2420 to get 188.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1880, and continue the process.

Moving on to step 12:
The number 558 fits into 1880 3 times, leaving a remainder of 206.
Put 3 as the next digit of the answer. 
Result so far: 76350.5143
Subtracting 1674 from 1880 leaves us with 206.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2060, and continue the process.

Advancing to step 13:
558 can be fit into 2060 3 times, resulting in a remainder of 386.
Write down 3 as next digit of the result. 
Result so far: 76350.51433
Subtracting 1674 from 2060 leaves us with 386.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3860, and continue the process.

The final result is 76350.51433 with a remainder of 0.000386.