We look at the division of 39518 by 42 
The aim is to understand the frequency of 42 in 39518.

Step 1:
3 divided by 42 is 0 with a remainder of 3.
Record the quotient 0 as the next digit in 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 / 42

On to step 2:
42 goes into 39 0 times with a remainder of 39.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we take 0 away from 39, we end up with 39.
Include the next digit (5) from the dividend after 39, then repeat: 395 / 42

Advancing to step 3:
395 divided by 42 is 9 with a remainder of 17.
Put 9 as the next digit of the answer. 
Result so far: 9.0
The remainder is 17 after subtracting 378 from 395.
Append the next digit (1) from the dividend to 17 and continue with: 171 / 42

Step 4:
When dividing 171 by 42, we get 4 with a remainder of 3.
The number 4 becomes the next digit in our result. 
Result so far: 94.0
Subtract 168 from 171 to get 3.
Grab the next digit (8) from the dividend, add it to 3, then carry on: 38 / 42

On to step 5:
38 divided by 42 is 0 with a remainder of 38.
Record the quotient 0 as the next digit in the result. 
Result so far: 940.0
Deduct 0 from 38 and we're left with 38.
Since there are no more digits in the dividend, we add a zero to the remainder making it 380, and continue the process.

Step 6:
When dividing 380 by 42, we get 9 with a remainder of 2.
The number 9 becomes the next digit in our result. 
Result so far: 940.9
The remainder is 2 after subtracting 378 from 380.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

On to step 7:
The number 42 fits into 20 0 times, leaving a remainder of 20.
Write down 0 as next digit of the result. 
Result so far: 940.9
Deduct 0 from 20 and we're left with 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Step 8:
42 goes into 200 4 times with a remainder of 32.
Record the quotient 4 as the next digit in the result. 
Result so far: 940.904
If we take 168 away from 200, we end up with 32.
Since there are no more digits in the dividend, we add a zero to the remainder making it 320, and continue the process.

Step 9:
42 can be fit into 320 7 times, resulting in a remainder of 26.
The number 7 becomes the next digit in our result. 
Result so far: 940.9047
If we subtract 294 from 320, we get 26.
Since there are no more digits in the dividend, we add a zero to the remainder making it 260, and continue the process.

Advancing to step 10:
When dividing 260 by 42, we get 6 with a remainder of 8.
Write down 6 as next digit of the result. 
Result so far: 940.90476
If we take 252 away from 260, we end up with 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Moving on to step 11:
When dividing 80 by 42, we get 1 with a remainder of 38.
Write down 1 as next digit of the result. 
Result so far: 940.904761
The remainder is 38 after subtracting 42 from 80.
Since there are no more digits in the dividend, we add a zero to the remainder making it 380, and continue the process.

On to step 12:
When dividing 380 by 42, we get 9 with a remainder of 2.
Use 9 as the next digit of our solution. 
Result so far: 940.9047619
Deduct 378 from 380 and we're left with 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

Let's proceed to step 13:
If we divide 20 by 42, we get 0 and a remainder of 20.
The number 0 becomes the next digit in our result. 
Result so far: 940.9047619
Subtract 0 from 20 to get 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

The final result is 940.9047619 with a remainder of 2e-08.