We look at the division of 80015980 by 213 
The aim is to understand the frequency of 213 in 80015980.

Advancing to step 1:
The number 213 fits into 8 0 times, leaving a remainder of 8.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we take 0 away from 8, we end up with 8.
Append the next digit (0) from the dividend to 8 and continue with: 80 / 213

Step 2:
The number 213 fits into 80 0 times, leaving a remainder of 80.
Use 0 as the next digit of our solution. 
Result so far: 0.0
The remainder is 80 after subtracting 0 from 80.
Append the next digit (0) from the dividend to 80 and continue with: 800 / 213

On to step 3:
213 can be fit into 800 3 times, resulting in a remainder of 161.
The number 3 becomes the next digit in our result. 
Result so far: 3.0
Subtracting 639 from 800 leaves us with 161.
Include the next digit (1) from the dividend after 161, then repeat: 1611 / 213

Moving on to step 4:
The number 213 fits into 1611 7 times, leaving a remainder of 120.
Write down 7 as next digit of the result. 
Result so far: 37.0
Deduct 1491 from 1611 and we're left with 120.
Fetch the next digit (5) from the dividend, attach it to 120 and continue: 1205 / 213

Step 5:
If we divide 1205 by 213, we get 5 and a remainder of 140.
The next digit of our result is 5. 
Result so far: 375.0
Subtracting 1065 from 1205 leaves us with 140.
Fetch the next digit (9) from the dividend, attach it to 140 and continue: 1409 / 213

Going ahead to step 6:
213 goes into 1409 6 times with a remainder of 131.
Write down 6 as next digit of the result. 
Result so far: 3756.0
If we subtract 1278 from 1409, we get 131.
Grab the next digit (8) from the dividend, add it to 131, then carry on: 1318 / 213

Advancing to step 7:
If we divide 1318 by 213, we get 6 and a remainder of 40.
Write down 6 as next digit of the result. 
Result so far: 37566.0
Deduct 1278 from 1318 and we're left with 40.
Grab the next digit (0) from the dividend, add it to 40, then carry on: 400 / 213

On to step 8:
400 divided by 213 is 1 with a remainder of 187.
Put 1 as the next digit of the answer. 
Result so far: 375661.0
Subtracting 213 from 400 leaves us with 187.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1870, and continue the process.

Going ahead to step 9:
213 goes into 1870 8 times with a remainder of 166.
Record the quotient 8 as the next digit in the result. 
Result so far: 375661.8
If we take 1704 away from 1870, we end up with 166.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1660, and continue the process.

Let's proceed to step 10:
The number 213 fits into 1660 7 times, leaving a remainder of 169.
The number 7 becomes the next digit in our result. 
Result so far: 375661.87
If we take 1491 away from 1660, we end up with 169.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1690, and continue the process.

On to step 11:
1690 divided by 213 is 7 with a remainder of 199.
The next digit of our result is 7. 
Result so far: 375661.877
Deduct 1491 from 1690 and we're left with 199.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1990, and continue the process.

Our division results in 375661.877 with a remaining 0.0199.