71868129 ÷ 861 
The aim is to understand the frequency of 861 in 71868129.

Advancing to step 1:
861 can be fit into 7 0 times, resulting in a remainder of 7.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Deduct 0 from 7 and we're left with 7.
Append the next digit (1) from the dividend to 7 and continue with: 71 / 861

Step 2:
861 goes into 71 0 times with a remainder of 71.
The next digit of our result is 0. 
Result so far: 0.0
If we subtract 0 from 71, we get 71.
Grab the next digit (8) from the dividend, add it to 71, then carry on: 718 / 861

Moving on to step 3:
718 divided by 861 is 0 with a remainder of 718.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtracting 0 from 718 leaves us with 718.
Fetch the next digit (6) from the dividend, attach it to 718 and continue: 7186 / 861

Let's proceed to step 4:
861 goes into 7186 8 times with a remainder of 298.
Write down 8 as next digit of the result. 
Result so far: 8.0
If we subtract 6888 from 7186, we get 298.
Take the next digit (8) from the dividend and append it to 298, then repeat: 2988 / 861

Advancing to step 5:
The number 861 fits into 2988 3 times, leaving a remainder of 405.
Record the quotient 3 as the next digit in the result. 
Result so far: 83.0
Subtract 2583 from 2988 to get 405.
Append the next digit (1) from the dividend to 405 and continue with: 4051 / 861

Advancing to step 6:
4051 divided by 861 is 4 with a remainder of 607.
Put 4 as the next digit of the answer. 
Result so far: 834.0
Deduct 3444 from 4051 and we're left with 607.
Fetch the next digit (2) from the dividend, attach it to 607 and continue: 6072 / 861

Step 7:
6072 divided by 861 is 7 with a remainder of 45.
Record the quotient 7 as the next digit in the result. 
Result so far: 8347.0
If we subtract 6027 from 6072, we get 45.
Take the next digit (9) from the dividend and append it to 45, then repeat: 459 / 861

Step 8:
If we divide 459 by 861, we get 0 and a remainder of 459.
Record the quotient 0 as the next digit in the result. 
Result so far: 83470.0
If we subtract 0 from 459, we get 459.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4590, and continue the process.

Let's proceed to step 9:
If we divide 4590 by 861, we get 5 and a remainder of 285.
Write down 5 as next digit of the result. 
Result so far: 83470.5
Subtracting 4305 from 4590 leaves us with 285.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2850, and continue the process.

Step 10:
If we divide 2850 by 861, we get 3 and a remainder of 267.
Use 3 as the next digit of our solution. 
Result so far: 83470.53
Deduct 2583 from 2850 and we're left with 267.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2670, and continue the process.

Let's proceed to step 11:
2670 divided by 861 is 3 with a remainder of 87.
Put 3 as the next digit of the answer. 
Result so far: 83470.533
The remainder is 87 after subtracting 2583 from 2670.
Since there are no more digits in the dividend, we add a zero to the remainder making it 870, and continue the process.

After the division, we end up with 83470.533 and a remainder of 0.0087.