502980 divided by 42 
The aim is to understand the frequency of 42 in 502980.

On to step 1:
The number 42 fits into 5 0 times, leaving a remainder of 5.
Write down 0 as next digit of the result. 
Result so far: 0.0
Deduct 0 from 5 and we're left with 5.
Grab the next digit (0) from the dividend, add it to 5, then carry on: 50 / 42

Let's proceed to step 2:
42 goes into 50 1 times with a remainder of 8.
Write down 1 as next digit of the result. 
Result so far: 1.0
The remainder is 8 after subtracting 42 from 50.
Grab the next digit (2) from the dividend, add it to 8, then carry on: 82 / 42

Step 3:
When dividing 82 by 42, we get 1 with a remainder of 40.
Use 1 as the next digit of our solution. 
Result so far: 11.0
If we take 42 away from 82, we end up with 40.
Take the next digit (9) from the dividend and append it to 40, then repeat: 409 / 42

Moving on to step 4:
When dividing 409 by 42, we get 9 with a remainder of 31.
Record the quotient 9 as the next digit in the result. 
Result so far: 119.0
Subtracting 378 from 409 leaves us with 31.
Bring next digit (8) of the dividend behind the 31 and repeat the process: 318 / 42

On to step 5:
42 goes into 318 7 times with a remainder of 24.
Write down 7 as next digit of the result. 
Result so far: 1197.0
The remainder is 24 after subtracting 294 from 318.
Grab the next digit (0) from the dividend, add it to 24, then carry on: 240 / 42

Advancing to step 6:
42 goes into 240 5 times with a remainder of 30.
Record the quotient 5 as the next digit in the result. 
Result so far: 11975.0
The remainder is 30 after subtracting 210 from 240.
Since there are no more digits in the dividend, we add a zero to the remainder making it 300, and continue the process.

Advancing to step 7:
300 divided by 42 is 7 with a remainder of 6.
Put 7 as the next digit of the answer. 
Result so far: 11975.7
If we subtract 294 from 300, we get 6.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

Advancing to step 8:
60 divided by 42 is 1 with a remainder of 18.
Record the quotient 1 as the next digit in the result. 
Result so far: 11975.71
Deduct 42 from 60 and we're left with 18.
Since there are no more digits in the dividend, we add a zero to the remainder making it 180, and continue the process.

Advancing to step 9:
When dividing 180 by 42, we get 4 with a remainder of 12.
The next digit of our result is 4. 
Result so far: 11975.714
If we take 168 away from 180, we end up with 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Going ahead to step 10:
42 goes into 120 2 times with a remainder of 36.
Put 2 as the next digit of the answer. 
Result so far: 11975.7142
Subtract 84 from 120 to get 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 11:
The number 42 fits into 360 8 times, leaving a remainder of 24.
Use 8 as the next digit of our solution. 
Result so far: 11975.71428
Subtracting 336 from 360 leaves us with 24.
Since there are no more digits in the dividend, we add a zero to the remainder making it 240, and continue the process.

On to step 12:
240 divided by 42 is 5 with a remainder of 30.
Put 5 as the next digit of the answer. 
Result so far: 11975.714285
The remainder is 30 after subtracting 210 from 240.
Since there are no more digits in the dividend, we add a zero to the remainder making it 300, and continue the process.

On to step 13:
The number 42 fits into 300 7 times, leaving a remainder of 6.
Record the quotient 7 as the next digit in the result. 
Result so far: 11975.7142857
Subtract 294 from 300 to get 6.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

Moving on to step 14:
60 divided by 42 is 1 with a remainder of 18.
The number 1 becomes the next digit in our result. 
Result so far: 11975.71428571
Subtracting 42 from 60 leaves us with 18.
Since there are no more digits in the dividend, we add a zero to the remainder making it 180, and continue the process.

After the division, we end up with 11975.71428571 and a remainder of 1.8e-08.