Let's divide 420871 by 66
The aim is to understand the frequency of 66 in 420871.

On to step 1:
66 goes into 4 0 times with a remainder of 4.
Record the quotient 0 as the next digit in the result. 
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

Advancing to step 2:
66 goes into 42 0 times with a remainder of 42.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 42 to get 42.
Include the next digit (0) from the dividend after 42, then repeat: 420 / 66

On to step 3:
When dividing 420 by 66, we get 6 with a remainder of 24.
The number 6 becomes the next digit in our result. 
Result so far: 6.0
If we take 396 away from 420, we end up with 24.
Grab the next digit (8) from the dividend, add it to 24, then carry on: 248 / 66

Step 4:
66 can be fit into 248 3 times, resulting in a remainder of 50.
Record the quotient 3 as the next digit in the result. 
Result so far: 63.0
If we subtract 198 from 248, we get 50.
Take the next digit (7) from the dividend and append it to 50, then repeat: 507 / 66

Moving on to step 5:
The number 66 fits into 507 7 times, leaving a remainder of 45.
Put 7 as the next digit of the answer. 
Result so far: 637.0
Subtracting 462 from 507 leaves us with 45.
Append the next digit (1) from the dividend to 45 and continue with: 451 / 66

On to step 6:
66 goes into 451 6 times with a remainder of 55.
The next digit of our result is 6. 
Result so far: 6376.0
Subtracting 396 from 451 leaves us with 55.
Since there are no more digits in the dividend, we add a zero to the remainder making it 550, and continue the process.

Advancing to step 7:
When dividing 550 by 66, we get 8 with a remainder of 22.
Write down 8 as next digit of the result. 
Result so far: 6376.8
Subtract 528 from 550 to get 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 8:
The number 66 fits into 220 3 times, leaving a remainder of 22.
Record the quotient 3 as the next digit in the result. 
Result so far: 6376.83
Subtract 198 from 220 to get 22.
Since there are no more digits in the dividend, we add a zero to the remainder making it 220, and continue the process.

Moving on to step 9:
220 divided by 66 is 3 with a remainder of 22.
Record the quotient 3 as the next digit in the result. 
Result so far: 6376.833
If we subtract 198 from 220, we get 22.
Since there are no more digits in the dividend, we add a zero to the remainder making it 220, and continue the process.

The quotient of the division is 6376.833, and the remainder is 0.0022.