We look at the division of 863690 by 42 
The aim is to understand the frequency of 42 in 863690.

Let's proceed to step 1:
8 divided by 42 is 0 with a remainder of 8.
The next digit of our result is 0. 
Result so far: 0.0
If we subtract 0 from 8, we get 8.
Append the next digit (6) from the dividend to 8 and continue with: 86 / 42

Advancing to step 2:
The number 42 fits into 86 2 times, leaving a remainder of 2.
The number 2 becomes the next digit in our result. 
Result so far: 2.0
Subtract 84 from 86 to get 2.
Take the next digit (3) from the dividend and append it to 2, then repeat: 23 / 42

Let's proceed to step 3:
The number 42 fits into 23 0 times, leaving a remainder of 23.
The number 0 becomes the next digit in our result. 
Result so far: 20.0
The remainder is 23 after subtracting 0 from 23.
Include the next digit (6) from the dividend after 23, then repeat: 236 / 42

Moving on to step 4:
If we divide 236 by 42, we get 5 and a remainder of 26.
Put 5 as the next digit of the answer. 
Result so far: 205.0
Subtract 210 from 236 to get 26.
Append the next digit (9) from the dividend to 26 and continue with: 269 / 42

Step 5:
If we divide 269 by 42, we get 6 and a remainder of 17.
Use 6 as the next digit of our solution. 
Result so far: 2056.0
If we subtract 252 from 269, we get 17.
Include the next digit (0) from the dividend after 17, then repeat: 170 / 42

Advancing to step 6:
42 goes into 170 4 times with a remainder of 2.
Write down 4 as next digit of the result. 
Result so far: 20564.0
Subtracting 168 from 170 leaves us 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.

Going ahead to step 7:
42 goes into 20 0 times with a remainder of 20.
Write down 0 as next digit of the result. 
Result so far: 20564.0
If we take 0 away from 20, we end up 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.

Advancing to step 8:
42 goes into 200 4 times with a remainder of 32.
Write down 4 as next digit of the result. 
Result so far: 20564.04
The remainder is 32 after subtracting 168 from 200.
Since there are no more digits in the dividend, we add a zero to the remainder making it 320, and continue the process.

On to step 9:
If we divide 320 by 42, we get 7 and a remainder of 26.
Record the quotient 7 as the next digit in the result. 
Result so far: 20564.047
If we take 294 away from 320, we end up with 26.
Since there are no more digits in the dividend, we add a zero to the remainder making it 260, and continue the process.

Let's proceed to step 10:
If we divide 260 by 42, we get 6 and a remainder of 8.
The next digit of our result is 6. 
Result so far: 20564.0476
Subtracting 252 from 260 leaves us 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:
The number 42 fits into 80 1 times, leaving a remainder of 38.
The next digit of our result is 1. 
Result so far: 20564.04761
Subtracting 42 from 80 leaves us 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.

Going ahead to step 12:
The number 42 fits into 380 9 times, leaving a remainder of 2.
Put 9 as the next digit of the answer. 
Result so far: 20564.047619
Subtract 378 from 380 to get 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

Moving on to step 13:
42 can be fit into 20 0 times, resulting in a remainder of 20.
Write down 0 as next digit of the result. 
Result so far: 20564.047619
If we take 0 away from 20, we end up 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 14:
The number 42 fits into 200 4 times, leaving a remainder of 32.
Put 4 as the next digit of the answer. 
Result so far: 20564.04761904
Deduct 168 from 200 and we're left 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.

After the division, we end up with 20564.04761904 and a remainder of 3.2e-08.