We're dividing 99139876 by 6 
The aim is to understand the frequency of 6 in 99139876.

Going ahead to step 1:
6 goes into 9 1 times with a remainder of 3.
The next digit of our result is 1. 
Result so far: 1.0
Subtract 6 from 9 to get 3.
Bring next digit (9) of the dividend behind the 3 and repeat the process: 39 / 6

On to step 2:
If we divide 39 by 6, we get 6 and a remainder of 3.
Use 6 as the next digit of our solution. 
Result so far: 16.0
The remainder is 3 after subtracting 36 from 39.
Grab the next digit (1) from the dividend, add it to 3, then carry on: 31 / 6

Step 3:
If we divide 31 by 6, we get 5 and a remainder of 1.
The number 5 becomes the next digit in our result. 
Result so far: 165.0
Deduct 30 from 31 and we're left with 1.
Append the next digit (3) from the dividend to 1 and continue with: 13 / 6

On to step 4:
13 divided by 6 is 2 with a remainder of 1.
The next digit of our result is 2. 
Result so far: 1652.0
If we subtract 12 from 13, we get 1.
Fetch the next digit (9) from the dividend, attach it to 1 and continue: 19 / 6

Moving on to step 5:
If we divide 19 by 6, we get 3 and a remainder of 1.
The next digit of our result is 3. 
Result so far: 16523.0
If we subtract 18 from 19, we get 1.
Append the next digit (8) from the dividend to 1 and continue with: 18 / 6

Advancing to step 6:
If we divide 18 by 6, we get 3 and a remainder of 0.
Put 3 as the next digit of the answer. 
Result so far: 165233.0
If we take 18 away from 18, we end up with 0.
Include the next digit (7) from the dividend after 0, then repeat: 7 / 6

On to step 7:
7 divided by 6 is 1 with a remainder of 1.
Put 1 as the next digit of the answer. 
Result so far: 1652331.0
Deduct 6 from 7 and we're left with 1.
Include the next digit (6) from the dividend after 1, then repeat: 16 / 6

Going ahead to step 8:
6 goes into 16 2 times with a remainder of 4.
The next digit of our result is 2. 
Result so far: 16523312.0
Subtracting 12 from 16 leaves us 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.

Going ahead to step 9:
6 can be fit into 40 6 times, resulting in a remainder of 4.
The number 6 becomes the next digit in our result. 
Result so far: 16523312.6
Deduct 36 from 40 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.

Moving on to step 10:
6 can be fit into 40 6 times, resulting in a remainder of 4.
The next digit of our result is 6. 
Result so far: 16523312.66
Subtracting 36 from 40 leaves us 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.

The quotient of the division is 16523312.66, and the remainder is 0.004.