421295 divided by 66 
The aim is to understand the frequency of 66 in 421295.

Going ahead to step 1:
4 divided by 66 is 0 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.
Include the next digit (2) from the dividend after 4, then repeat: 42 / 66

Moving on to step 2:
42 divided by 66 is 0 with a remainder of 42.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we take 0 away from 42, we end up with 42.
Take the next digit (1) from the dividend and append it to 42, then repeat: 421 / 66

On to step 3:
66 goes into 421 6 times with a remainder of 25.
The number 6 becomes the next digit in our result. 
Result so far: 6.0
The remainder is 25 after subtracting 396 from 421.
Fetch the next digit (2) from the dividend, attach it to 25 and continue: 252 / 66

Advancing to step 4:
The number 66 fits into 252 3 times, leaving a remainder of 54.
The next digit of our result is 3. 
Result so far: 63.0
Subtracting 198 from 252 leaves us with 54.
Fetch the next digit (9) from the dividend, attach it to 54 and continue: 549 / 66

Let's proceed to step 5:
The number 66 fits into 549 8 times, leaving a remainder of 21.
Put 8 as the next digit of the answer. 
Result so far: 638.0
If we take 528 away from 549, we end up with 21.
Bring next digit (5) of the dividend behind the 21 and repeat the process: 215 / 66

On to step 6:
When dividing 215 by 66, we get 3 with a remainder of 17.
Write down 3 as next digit of the result. 
Result so far: 6383.0
If we subtract 198 from 215, we get 17.
Since there are no more digits in the dividend, we add a zero to the remainder making it 170, and continue the process.

Step 7:
If we divide 170 by 66, we get 2 and a remainder of 38.
The next digit of our result is 2. 
Result so far: 6383.2
If we subtract 132 from 170, we get 38.
Since there are no more digits in the dividend, we add a zero to the remainder making it 380, and continue the process.

Let's proceed to step 8:
The number 66 fits into 380 5 times, leaving a remainder of 50.
The number 5 becomes the next digit in our result. 
Result so far: 6383.25
Subtracting 330 from 380 leaves us with 50.
Since there are no more digits in the dividend, we add a zero to the remainder making it 500, and continue the process.

Step 9:
66 can be fit into 500 7 times, resulting in a remainder of 38.
The next digit of our result is 7. 
Result so far: 6383.257
If we subtract 462 from 500, we get 38.
Since there are no more digits in the dividend, we add a zero to the remainder making it 380, and continue the process.

Advancing to step 10:
If we divide 380 by 66, we get 5 and a remainder of 50.
Record the quotient 5 as the next digit in the result. 
Result so far: 6383.2575
The remainder is 50 after subtracting 330 from 380.
Since there are no more digits in the dividend, we add a zero to the remainder making it 500, and continue the process.

Advancing to step 11:
500 divided by 66 is 7 with a remainder of 38.
The number 7 becomes the next digit in our result. 
Result so far: 6383.25757
If we subtract 462 from 500, we get 38.
Since there are no more digits in the dividend, we add a zero to the remainder making it 380, and continue the process.

Moving on to step 12:
66 goes into 380 5 times with a remainder of 50.
Record the quotient 5 as the next digit in the result. 
Result so far: 6383.257575
Subtract 330 from 380 to get 50.
Since there are no more digits in the dividend, we add a zero to the remainder making it 500, and continue the process.

On to step 13:
66 goes into 500 7 times with a remainder of 38.
Write down 7 as next digit of the result. 
Result so far: 6383.2575757
If we take 462 away from 500, we end up 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.

Moving on to step 14:
66 goes into 380 5 times with a remainder of 50.
Use 5 as the next digit of our solution. 
Result so far: 6383.25757575
If we subtract 330 from 380, we get 50.
Since there are no more digits in the dividend, we add a zero to the remainder making it 500, and continue the process.

After the division, we end up with 6383.25757575 and a remainder of 5e-08.