1020915 divided by 210 
The aim is to understand the frequency of 210 in 1020915.

On to step 1:
1 divided by 210 is 0 with a remainder of 1.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtract 0 from 1 to get 1.
Append the next digit (0) from the dividend to 1 and continue with: 10 / 210

Advancing to step 2:
210 can be fit into 10 0 times, resulting in a remainder of 10.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtracting 0 from 10 leaves us with 10.
Include the next digit (2) from the dividend after 10, then repeat: 102 / 210

Going ahead to step 3:
The number 210 fits into 102 0 times, leaving a remainder of 102.
The next digit of our result is 0. 
Result so far: 0.0
Subtract 0 from 102 to get 102.
Include the next digit (0) from the dividend after 102, then repeat: 1020 / 210

Moving on to step 4:
210 goes into 1020 4 times with a remainder of 180.
Put 4 as the next digit of the answer. 
Result so far: 4.0
Subtracting 840 from 1020 leaves us with 180.
Include the next digit (9) from the dividend after 180, then repeat: 1809 / 210

Moving on to step 5:
If we divide 1809 by 210, we get 8 and a remainder of 129.
Use 8 as the next digit of our solution. 
Result so far: 48.0
If we subtract 1680 from 1809, we get 129.
Grab the next digit (1) from the dividend, add it to 129, then carry on: 1291 / 210

Advancing to step 6:
When dividing 1291 by 210, we get 6 with a remainder of 31.
Record the quotient 6 as the next digit in the result. 
Result so far: 486.0
The remainder is 31 after subtracting 1260 from 1291.
Bring next digit (5) of the dividend behind the 31 and repeat the process: 315 / 210

Advancing to step 7:
210 can be fit into 315 1 times, resulting in a remainder of 105.
Use 1 as the next digit of our solution. 
Result so far: 4861.0
The remainder is 105 after subtracting 210 from 315.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1050, and continue the process.

Let's proceed to step 8:
210 can be fit into 1050 5 times, resulting in a remainder of 0.
Use 5 as the next digit of our solution. 
Result so far: 4861.5
The remainder is 0 after subtracting 1050 from 1050.
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 9:
If we divide 0 by 210, we get 0 and a remainder of 0.
The next digit of our result is 0. 
Result so far: 4861.5
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.

On to step 10:
210 goes into 0 0 times with a remainder of 0.
Write down 0 as next digit of the result. 
Result so far: 4861.5
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.

Our division results in 4861.5 with a remaining 0.0.