35721 ÷ 20 
The aim is to understand the frequency of 20 in 35721.

Let's proceed to step 1:
3 divided by 20 is 0 with a remainder of 3.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we subtract 0 from 3, we get 3.
Take the next digit (5) from the dividend and append it to 3, then repeat: 35 / 20

Advancing to step 2:
The number 20 fits into 35 1 times, leaving a remainder of 15.
Put 1 as the next digit of the answer. 
Result so far: 1.0
If we take 20 away from 35, we end up with 15.
Take the next digit (7) from the dividend and append it to 15, then repeat: 157 / 20

Advancing to step 3:
20 goes into 157 7 times with a remainder of 17.
Put 7 as the next digit of the answer. 
Result so far: 17.0
The remainder is 17 after subtracting 140 from 157.
Fetch the next digit (2) from the dividend, attach it to 17 and continue: 172 / 20

Moving on to step 4:
The number 20 fits into 172 8 times, leaving a remainder of 12.
Put 8 as the next digit of the answer. 
Result so far: 178.0
If we take 160 away from 172, we end up with 12.
Take the next digit (1) from the dividend and append it to 12, then repeat: 121 / 20

Step 5:
When dividing 121 by 20, we get 6 with a remainder of 1.
Use 6 as the next digit of our solution. 
Result so far: 1786.0
If we take 120 away from 121, we end up 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 6:
10 divided by 20 is 0 with a remainder of 10.
Put 0 as the next digit of the answer. 
Result so far: 1786.0
The remainder is 10 after subtracting 0 from 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:
When dividing 100 by 20, we get 5 with a remainder of 0.
Put 5 as the next digit of the answer. 
Result so far: 1786.05
Deduct 100 from 100 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.

Let's proceed to step 8:
When dividing 0 by 20, we get 0 with a remainder of 0.
Put 0 as the next digit of the answer. 
Result so far: 1786.05
The remainder is 0 after subtracting 0 from 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

On to step 9:
The number 20 fits into 0 0 times, leaving a remainder of 0.
Put 0 as the next digit of the answer. 
Result so far: 1786.05
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 outcome is 1786.05, with a leftover of 0.0.