645667 divided by 4 
The aim is to understand the frequency of 4 in 645667.

Advancing to step 1:
If we divide 6 by 4, we get 1 and a remainder of 2.
Write down 1 as next digit of the result. 
Result so far: 1.0
If we take 4 away from 6, we end up with 2.
Include the next digit (4) from the dividend after 2, then repeat: 24 / 4

Step 2:
When dividing 24 by 4, we get 6 with a remainder of 0.
Put 6 as the next digit of the answer. 
Result so far: 16.0
Subtract 24 from 24 to get 0.
Bring next digit (5) of the dividend behind the 0 and repeat the process: 5 / 4

Let's proceed to step 3:
When dividing 5 by 4, we get 1 with a remainder of 1.
Write down 1 as next digit of the result. 
Result so far: 161.0
If we take 4 away from 5, we end up with 1.
Append the next digit (6) from the dividend to 1 and continue with: 16 / 4

Going ahead to step 4:
The number 4 fits into 16 4 times, leaving a remainder of 0.
Put 4 as the next digit of the answer. 
Result so far: 1614.0
If we take 16 away from 16, we end up with 0.
Grab the next digit (6) from the dividend, add it to 0, then carry on: 6 / 4

Going ahead to step 5:
4 goes into 6 1 times with a remainder of 2.
Write down 1 as next digit of the result. 
Result so far: 16141.0
Deduct 4 from 6 and we're left with 2.
Take the next digit (7) from the dividend and append it to 2, then repeat: 27 / 4

On to step 6:
When dividing 27 by 4, we get 6 with a remainder of 3.
Use 6 as the next digit of our solution. 
Result so far: 161416.0
Subtracting 24 from 27 leaves us with 3.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

Advancing to step 7:
The number 4 fits into 30 7 times, leaving a remainder of 2.
Write down 7 as next digit of the result. 
Result so far: 161416.7
The remainder is 2 after subtracting 28 from 30.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

On to step 8:
If we divide 20 by 4, we get 5 and a remainder of 0.
Put 5 as the next digit of the answer. 
Result so far: 161416.75
The remainder is 0 after subtracting 20 from 20.
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 goes into 0 0 times with a remainder of 0.
Write down 0 as next digit of the result. 
Result so far: 161416.75
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.

Step 10:
4 can be fit into 0 0 times, resulting in a remainder of 0.
Write down 0 as next digit of the result. 
Result so far: 161416.75
Subtract 0 from 0 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.

The final result is 161416.75 with a remainder of 0.0.