3781583 divided by 212 
The aim is to understand the frequency of 212 in 3781583.

On to step 1:
3 divided by 212 is 0 with a remainder of 3.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Deduct 0 from 3 and we're left with 3.
Grab the next digit (7) from the dividend, add it to 3, then carry on: 37 / 212

Moving on to step 2:
37 divided by 212 is 0 with a remainder of 37.
The next digit of our result is 0. 
Result so far: 0.0
Subtracting 0 from 37 leaves us with 37.
Grab the next digit (8) from the dividend, add it to 37, then carry on: 378 / 212

On to step 3:
If we divide 378 by 212, we get 1 and a remainder of 166.
Write down 1 as next digit of the result. 
Result so far: 1.0
If we subtract 212 from 378, we get 166.
Grab the next digit (1) from the dividend, add it to 166, then carry on: 1661 / 212

Moving on to step 4:
When dividing 1661 by 212, we get 7 with a remainder of 177.
Use 7 as the next digit of our solution. 
Result so far: 17.0
If we subtract 1484 from 1661, we get 177.
Append the next digit (5) from the dividend to 177 and continue with: 1775 / 212

Going ahead to step 5:
If we divide 1775 by 212, we get 8 and a remainder of 79.
Use 8 as the next digit of our solution. 
Result so far: 178.0
If we take 1696 away from 1775, we end up with 79.
Fetch the next digit (8) from the dividend, attach it to 79 and continue: 798 / 212

Going ahead to step 6:
212 can be fit into 798 3 times, resulting in a remainder of 162.
Use 3 as the next digit of our solution. 
Result so far: 1783.0
Deduct 636 from 798 and we're left with 162.
Fetch the next digit (3) from the dividend, attach it to 162 and continue: 1623 / 212

Step 7:
The number 212 fits into 1623 7 times, leaving a remainder of 139.
Put 7 as the next digit of the answer. 
Result so far: 17837.0
Subtracting 1484 from 1623 leaves us with 139.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1390, and continue the process.

Let's proceed to step 8:
1390 divided by 212 is 6 with a remainder of 118.
Record the quotient 6 as the next digit in the result. 
Result so far: 17837.6
Subtract 1272 from 1390 to get 118.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1180, and continue the process.

Step 9:
212 goes into 1180 5 times with a remainder of 120.
The next digit of our result is 5. 
Result so far: 17837.65
The remainder is 120 after subtracting 1060 from 1180.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1200, and continue the process.

Moving on to step 10:
The number 212 fits into 1200 5 times, leaving a remainder of 140.
Put 5 as the next digit of the answer. 
Result so far: 17837.655
If we subtract 1060 from 1200, we get 140.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1400, and continue the process.

The final outcome is 17837.655, with a leftover of 0.014.