We look at the division of 661183 by 42 
The aim is to understand the frequency of 42 in 661183.

On to step 1:
The number 42 fits into 6 0 times, leaving a remainder of 6.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we take 0 away from 6, we end up with 6.
Take the next digit (6) from the dividend and append it to 6, then repeat: 66 / 42

Advancing to step 2:
When dividing 66 by 42, we get 1 with a remainder of 24.
Write down 1 as next digit of the result. 
Result so far: 1.0
Deduct 42 from 66 and we're left with 24.
Grab the next digit (1) from the dividend, add it to 24, then carry on: 241 / 42

Step 3:
If we divide 241 by 42, we get 5 and a remainder of 31.
Record the quotient 5 as the next digit in the result. 
Result so far: 15.0
The remainder is 31 after subtracting 210 from 241.
Bring next digit (1) of the dividend behind the 31 and repeat the process: 311 / 42

Step 4:
42 goes into 311 7 times with a remainder of 17.
The number 7 becomes the next digit in our result. 
Result so far: 157.0
Deduct 294 from 311 and we're left with 17.
Bring next digit (8) of the dividend behind the 17 and repeat the process: 178 / 42

Advancing to step 5:
If we divide 178 by 42, we get 4 and a remainder of 10.
Record the quotient 4 as the next digit in the result. 
Result so far: 1574.0
Subtracting 168 from 178 leaves us with 10.
Append the next digit (3) from the dividend to 10 and continue with: 103 / 42

On to step 6:
When dividing 103 by 42, we get 2 with a remainder of 19.
Use 2 as the next digit of our solution. 
Result so far: 15742.0
The remainder is 19 after subtracting 84 from 103.
Since there are no more digits in the dividend, we add a zero to the remainder making it 190, and continue the process.

Moving on to step 7:
When dividing 190 by 42, we get 4 with a remainder of 22.
The next digit of our result is 4. 
Result so far: 15742.4
If we take 168 away from 190, we end up with 22.
Since there are no more digits in the dividend, we add a zero to the remainder making it 220, and continue the process.

Going ahead to step 8:
The number 42 fits into 220 5 times, leaving a remainder of 10.
Use 5 as the next digit of our solution. 
Result so far: 15742.45
If we subtract 210 from 220, we get 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Moving on to step 9:
42 goes into 100 2 times with a remainder of 16.
Use 2 as the next digit of our solution. 
Result so far: 15742.452
Subtract 84 from 100 to get 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

Going ahead to step 10:
160 divided by 42 is 3 with a remainder of 34.
The next digit of our result is 3. 
Result so far: 15742.4523
Subtracting 126 from 160 leaves us with 34.
Since there are no more digits in the dividend, we add a zero to the remainder making it 340, and continue the process.

Moving on to step 11:
The number 42 fits into 340 8 times, leaving a remainder of 4.
Write down 8 as next digit of the result. 
Result so far: 15742.45238
The remainder is 4 after subtracting 336 from 340.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Moving on to step 12:
The number 42 fits into 40 0 times, leaving a remainder of 40.
The number 0 becomes the next digit in our result. 
Result so far: 15742.45238
If we subtract 0 from 40, we get 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

On to step 13:
42 goes into 400 9 times with a remainder of 22.
Record the quotient 9 as the next digit in the result. 
Result so far: 15742.4523809
Deduct 378 from 400 and we're left with 22.
Since there are no more digits in the dividend, we add a zero to the remainder making it 220, and continue the process.

Advancing to step 14:
42 can be fit into 220 5 times, resulting in a remainder of 10.
Write down 5 as next digit of the result. 
Result so far: 15742.45238095
The remainder is 10 after subtracting 210 from 220.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

The final result is 15742.45238095 with a remainder of 1e-08.