We look at the division of 1438683 by 221 
The aim is to understand the frequency of 221 in 1438683.

Going ahead to step 1:
221 can be fit into 1 0 times, resulting in a remainder of 1.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Deduct 0 from 1 and we're left with 1.
Append the next digit (4) from the dividend to 1 and continue with: 14 / 221

Going ahead to step 2:
When dividing 14 by 221, we get 0 with a remainder of 14.
The next digit of our result is 0. 
Result so far: 0.0
Subtracting 0 from 14 leaves us with 14.
Append the next digit (3) from the dividend to 14 and continue with: 143 / 221

Going ahead to step 3:
221 goes into 143 0 times with a remainder of 143.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we subtract 0 from 143, we get 143.
Include the next digit (8) from the dividend after 143, then repeat: 1438 / 221

Let's proceed to step 4:
If we divide 1438 by 221, we get 6 and a remainder of 112.
Use 6 as the next digit of our solution. 
Result so far: 6.0
Subtract 1326 from 1438 to get 112.
Append the next digit (6) from the dividend to 112 and continue with: 1126 / 221

Let's proceed to step 5:
When dividing 1126 by 221, we get 5 with a remainder of 21.
Record the quotient 5 as the next digit in the result. 
Result so far: 65.0
Deduct 1105 from 1126 and we're left with 21.
Take the next digit (8) from the dividend and append it to 21, then repeat: 218 / 221

Let's proceed to step 6:
221 goes into 218 0 times with a remainder of 218.
Record the quotient 0 as the next digit in the result. 
Result so far: 650.0
Subtract 0 from 218 to get 218.
Include the next digit (3) from the dividend after 218, then repeat: 2183 / 221

Step 7:
221 goes into 2183 9 times with a remainder of 194.
Record the quotient 9 as the next digit in the result. 
Result so far: 6509.0
If we take 1989 away from 2183, we end up with 194.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1940, and continue the process.

Going ahead to step 8:
221 can be fit into 1940 8 times, resulting in a remainder of 172.
Record the quotient 8 as the next digit in the result. 
Result so far: 6509.8
Deduct 1768 from 1940 and we're left with 172.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1720, and continue the process.

Advancing to step 9:
1720 divided by 221 is 7 with a remainder of 173.
Put 7 as the next digit of the answer. 
Result so far: 6509.87
Subtracting 1547 from 1720 leaves us with 173.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1730, and continue the process.

Going ahead to step 10:
221 can be fit into 1730 7 times, resulting in a remainder of 183.
Write down 7 as next digit of the result. 
Result so far: 6509.877
Deduct 1547 from 1730 and we're left with 183.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1830, and continue the process.

After the division, we end up with 6509.877 and a remainder of 0.0183.