491251 ÷ 3 
The aim is to understand the frequency of 3 in 491251.

On to step 1:
The number 3 fits into 4 1 times, leaving a remainder of 1.
Write down 1 as next digit of the result. 
Result so far: 1.0
Subtracting 3 from 4 leaves us with 1.
Append the next digit (9) from the dividend to 1 and continue with: 19 / 3

Going ahead to step 2:
When dividing 19 by 3, we get 6 with a remainder of 1.
The number 6 becomes the next digit in our result. 
Result so far: 16.0
Deduct 18 from 19 and we're left with 1.
Bring next digit (1) of the dividend behind the 1 and repeat the process: 11 / 3

Let's proceed to step 3:
3 goes into 11 3 times with a remainder of 2.
The number 3 becomes the next digit in our result. 
Result so far: 163.0
The remainder is 2 after subtracting 9 from 11.
Grab the next digit (2) from the dividend, add it to 2, then carry on: 22 / 3

Going ahead to step 4:
3 goes into 22 7 times with a remainder of 1.
Record the quotient 7 as the next digit in the result. 
Result so far: 1637.0
Deduct 21 from 22 and we're left with 1.
Take the next digit (5) from the dividend and append it to 1, then repeat: 15 / 3

Moving on to step 5:
3 goes into 15 5 times with a remainder of 0.
Use 5 as the next digit of our solution. 
Result so far: 16375.0
Deduct 15 from 15 and we're left with 0.
Fetch the next digit (1) from the dividend, attach it to 0 and continue: 1 / 3

Going ahead to step 6:
The number 3 fits into 1 0 times, leaving a remainder of 1.
Write down 0 as next digit of the result. 
Result so far: 163750.0
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.

Let's proceed to step 7:
3 goes into 10 3 times with a remainder of 1.
The next digit of our result is 3. 
Result so far: 163750.3
Subtracting 9 from 10 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.

On to step 8:
If we divide 10 by 3, we get 3 and a remainder of 1.
The number 3 becomes the next digit in our result. 
Result so far: 163750.33
Subtract 9 from 10 to get 1.
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 163750.33, and the remainder is 0.001.