We look at the division of 989521 by 3 
The aim is to understand the frequency of 3 in 989521.

Going ahead to step 1:
3 goes into 9 3 times with a remainder of 0.
Write down 3 as next digit of the result. 
Result so far: 3.0
If we subtract 9 from 9, we get 0.
Bring next digit (8) of the dividend behind the 0 and repeat the process: 8 / 3

Advancing to step 2:
If we divide 8 by 3, we get 2 and a remainder of 2.
Write down 2 as next digit of the result. 
Result so far: 32.0
The remainder is 2 after subtracting 6 from 8.
Append the next digit (9) from the dividend to 2 and continue with: 29 / 3

Moving on to step 3:
3 can be fit into 29 9 times, resulting in a remainder of 2.
Use 9 as the next digit of our solution. 
Result so far: 329.0
Subtracting 27 from 29 leaves us with 2.
Include the next digit (5) from the dividend after 2, then repeat: 25 / 3

Going ahead to step 4:
3 can be fit into 25 8 times, resulting in a remainder of 1.
Put 8 as the next digit of the answer. 
Result so far: 3298.0
If we take 24 away from 25, we end up with 1.
Take the next digit (2) from the dividend and append it to 1, then repeat: 12 / 3

Advancing to step 5:
When dividing 12 by 3, we get 4 with a remainder of 0.
Record the quotient 4 as the next digit in the result. 
Result so far: 32984.0
Subtracting 12 from 12 leaves us with 0.
Append the next digit (1) from the dividend to 0 and continue with: 1 / 3

Step 6:
The number 3 fits into 1 0 times, leaving a remainder of 1.
Record the quotient 0 as the next digit in the result. 
Result so far: 329840.0
Subtracting 0 from 1 leaves us with 1.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

Moving on to step 7:
3 can be fit into 10 3 times, resulting in a remainder of 1.
Record the quotient 3 as the next digit in the result. 
Result so far: 329840.3
The remainder is 1 after subtracting 9 from 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

Advancing to step 8:
The number 3 fits into 10 3 times, leaving a remainder of 1.
The next digit of our result is 3. 
Result so far: 329840.33
The remainder is 1 after subtracting 9 from 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

The quotient of the division is 329840.33, and the remainder is 0.001.