172861 ÷ 66 
The aim is to understand the frequency of 66 in 172861.

Step 1:
The number 66 fits into 1 0 times, leaving a remainder of 1.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we take 0 away from 1, we end up with 1.
Fetch the next digit (7) from the dividend, attach it to 1 and continue: 17 / 66

Advancing to step 2:
If we divide 17 by 66, we get 0 and a remainder of 17.
Put 0 as the next digit of the answer. 
Result so far: 0.0
The remainder is 17 after subtracting 0 from 17.
Append the next digit (2) from the dividend to 17 and continue with: 172 / 66

Going ahead to step 3:
66 goes into 172 2 times with a remainder of 40.
Write down 2 as next digit of the result. 
Result so far: 2.0
Deduct 132 from 172 and we're left with 40.
Append the next digit (8) from the dividend to 40 and continue with: 408 / 66

Going ahead to step 4:
66 goes into 408 6 times with a remainder of 12.
Use 6 as the next digit of our solution. 
Result so far: 26.0
Subtracting 396 from 408 leaves us with 12.
Take the next digit (6) from the dividend and append it to 12, then repeat: 126 / 66

Let's proceed to step 5:
126 divided by 66 is 1 with a remainder of 60.
Use 1 as the next digit of our solution. 
Result so far: 261.0
Subtract 66 from 126 to get 60.
Bring next digit (1) of the dividend behind the 60 and repeat the process: 601 / 66

Advancing to step 6:
66 goes into 601 9 times with a remainder of 7.
Record the quotient 9 as the next digit in the result. 
Result so far: 2619.0
If we take 594 away from 601, we end up with 7.
Since there are no more digits in the dividend, we add a zero to the remainder making it 70, and continue the process.

Advancing to step 7:
When dividing 70 by 66, we get 1 with a remainder of 4.
Write down 1 as next digit of the result. 
Result so far: 2619.1
Subtract 66 from 70 to get 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Advancing to step 8:
66 goes into 40 0 times with a remainder of 40.
Put 0 as the next digit of the answer. 
Result so far: 2619.1
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.

Moving on to step 9:
If we divide 400 by 66, we get 6 and a remainder of 4.
The number 6 becomes the next digit in our result. 
Result so far: 2619.106
The remainder is 4 after subtracting 396 from 400.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Step 10:
66 goes into 40 0 times with a remainder of 40.
Record the quotient 0 as the next digit in the result. 
Result so far: 2619.106
Subtracting 0 from 40 leaves us with 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

Going ahead to step 11:
400 divided by 66 is 6 with a remainder of 4.
Record the quotient 6 as the next digit in the result. 
Result so far: 2619.10606
Deduct 396 from 400 and we're left with 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Step 12:
When dividing 40 by 66, we get 0 with a remainder of 40.
Write down 0 as next digit of the result. 
Result so far: 2619.10606
Subtracting 0 from 40 leaves us with 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

Advancing to step 13:
The number 66 fits into 400 6 times, leaving a remainder of 4.
Write down 6 as next digit of the result. 
Result so far: 2619.1060606
If we subtract 396 from 400, we get 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Advancing to step 14:
66 can be fit into 40 0 times, resulting in a remainder of 40.
Use 0 as the next digit of our solution. 
Result so far: 2619.1060606
If we take 0 away from 40, we end up with 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

The final outcome is 2619.1060606, with a leftover of 4e-08.