We're dividing 878494 by 12 
The aim is to understand the frequency of 12 in 878494.

Step 1:
When dividing 8 by 12, we get 0 with a remainder of 8.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we subtract 0 from 8, we get 8.
Fetch the next digit (7) from the dividend, attach it to 8 and continue: 87 / 12

Going ahead to step 2:
The number 12 fits into 87 7 times, leaving a remainder of 3.
Use 7 as the next digit of our solution. 
Result so far: 7.0
Subtract 84 from 87 to get 3.
Take the next digit (8) from the dividend and append it to 3, then repeat: 38 / 12

Advancing to step 3:
38 divided by 12 is 3 with a remainder of 2.
The number 3 becomes the next digit in our result. 
Result so far: 73.0
If we take 36 away from 38, we end up with 2.
Take the next digit (4) from the dividend and append it to 2, then repeat: 24 / 12

On to step 4:
12 can be fit into 24 2 times, resulting in a remainder of 0.
Write down 2 as next digit of the result. 
Result so far: 732.0
Subtract 24 from 24 to get 0.
Bring next digit (9) of the dividend behind the 0 and repeat the process: 9 / 12

Advancing to step 5:
12 can be fit into 9 0 times, resulting in a remainder of 9.
Use 0 as the next digit of our solution. 
Result so far: 7320.0
Subtracting 0 from 9 leaves us with 9.
Grab the next digit (4) from the dividend, add it to 9, then carry on: 94 / 12

Step 6:
The number 12 fits into 94 7 times, leaving a remainder of 10.
Record the quotient 7 as the next digit in the result. 
Result so far: 73207.0
If we take 84 away from 94, we end up with 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

On to step 7:
100 divided by 12 is 8 with a remainder of 4.
Record the quotient 8 as the next digit in the result. 
Result so far: 73207.8
Subtract 96 from 100 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.

On to step 8:
12 can be fit into 40 3 times, resulting in a remainder of 4.
The number 3 becomes the next digit in our result. 
Result so far: 73207.83
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.

Advancing to step 9:
If we divide 40 by 12, we get 3 and a remainder of 4.
Put 3 as the next digit of the answer. 
Result so far: 73207.833
Subtract 36 from 40 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.

The quotient of the division is 73207.833, and the remainder is 0.0004.