91644742 ÷ 213 
The aim is to understand the frequency of 213 in 91644742.

Going ahead to step 1:
When dividing 9 by 213, we get 0 with a remainder of 9.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Deduct 0 from 9 and we're left with 9.
Append the next digit (1) from the dividend to 9 and continue with: 91 / 213

Moving on to step 2:
When dividing 91 by 213, we get 0 with a remainder of 91.
The next digit of our result is 0. 
Result so far: 0.0
The remainder is 91 after subtracting 0 from 91.
Append the next digit (6) from the dividend to 91 and continue with: 916 / 213

Going ahead to step 3:
916 divided by 213 is 4 with a remainder of 64.
The number 4 becomes the next digit in our result. 
Result so far: 4.0
The remainder is 64 after subtracting 852 from 916.
Include the next digit (4) from the dividend after 64, then repeat: 644 / 213

Going ahead to step 4:
When dividing 644 by 213, we get 3 with a remainder of 5.
Use 3 as the next digit of our solution. 
Result so far: 43.0
Deduct 639 from 644 and we're left with 5.
Include the next digit (4) from the dividend after 5, then repeat: 54 / 213

On to step 5:
The number 213 fits into 54 0 times, leaving a remainder of 54.
Use 0 as the next digit of our solution. 
Result so far: 430.0
The remainder is 54 after subtracting 0 from 54.
Fetch the next digit (7) from the dividend, attach it to 54 and continue: 547 / 213

Going ahead to step 6:
213 goes into 547 2 times with a remainder of 121.
The number 2 becomes the next digit in our result. 
Result so far: 4302.0
The remainder is 121 after subtracting 426 from 547.
Take the next digit (4) from the dividend and append it to 121, then repeat: 1214 / 213

Going ahead to step 7:
213 can be fit into 1214 5 times, resulting in a remainder of 149.
The number 5 becomes the next digit in our result. 
Result so far: 43025.0
If we subtract 1065 from 1214, we get 149.
Include the next digit (2) from the dividend after 149, then repeat: 1492 / 213

Moving on to step 8:
When dividing 1492 by 213, we get 7 with a remainder of 1.
Record the quotient 7 as the next digit in the result. 
Result so far: 430257.0
The remainder is 1 after subtracting 1491 from 1492.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

Let's proceed to step 9:
If we divide 10 by 213, we get 0 and a remainder of 10.
Record the quotient 0 as the next digit in the result. 
Result so far: 430257.0
If we take 0 away from 10, we end up with 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Going ahead to step 10:
100 divided by 213 is 0 with a remainder of 100.
Record the quotient 0 as the next digit in the result. 
Result so far: 430257.0
Deduct 0 from 100 and we're left with 100.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1000, and continue the process.

The final outcome is 430257.0, with a leftover of 0.1.