We divide 601721 by 4
The aim is to understand the frequency of 4 in 601721.

Advancing to step 1:
The number 4 fits into 6 1 times, leaving a remainder of 2.
Put 1 as the next digit of the answer. 
Result so far: 1.0
Deduct 4 from 6 and we're left with 2.
Grab the next digit (0) from the dividend, add it to 2, then carry on: 20 / 4

Step 2:
When dividing 20 by 4, we get 5 with a remainder of 0.
The next digit of our result is 5. 
Result so far: 15.0
If we take 20 away from 20, we end up with 0.
Take the next digit (1) from the dividend and append it to 0, then repeat: 1 / 4

On to step 3:
When dividing 1 by 4, we get 0 with a remainder of 1.
Record the quotient 0 as the next digit in the result. 
Result so far: 150.0
Subtract 0 from 1 to get 1.
Bring next digit (7) of the dividend behind the 1 and repeat the process: 17 / 4

On to step 4:
4 goes into 17 4 times with a remainder of 1.
Put 4 as the next digit of the answer. 
Result so far: 1504.0
The remainder is 1 after subtracting 16 from 17.
Take the next digit (2) from the dividend and append it to 1, then repeat: 12 / 4

Moving on to step 5:
4 goes into 12 3 times with a remainder of 0.
The next digit of our result is 3. 
Result so far: 15043.0
Subtracting 12 from 12 leaves us with 0.
Bring next digit (1) of the dividend behind the 0 and repeat the process: 1 / 4

Step 6:
If we divide 1 by 4, we get 0 and a remainder of 1.
Write down 0 as next digit of the result. 
Result so far: 150430.0
Deduct 0 from 1 and we're left 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 7:
4 can be fit into 10 2 times, resulting in a remainder of 2.
Put 2 as the next digit of the answer. 
Result so far: 150430.2
Subtract 8 from 10 to get 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

Going ahead to step 8:
The number 4 fits into 20 5 times, leaving a remainder of 0.
The next digit of our result is 5. 
Result so far: 150430.25
Subtract 20 from 20 to get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Going ahead to step 9:
4 can be fit into 0 0 times, resulting in a remainder of 0.
Record the quotient 0 as the next digit in the result. 
Result so far: 150430.25
If we take 0 away from 0, we end up with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Advancing to step 10:
The number 4 fits into 0 0 times, leaving a remainder of 0.
Write down 0 as next digit of the result. 
Result so far: 150430.25
Deduct 0 from 0 and we're left with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

The final outcome is 150430.25, with a leftover of 0.0.