We look at the division of 66921082 by 386 
The aim is to understand the frequency of 386 in 66921082.

Step 1:
386 goes into 6 0 times with a remainder of 6.
The next digit of our result is 0. 
Result so far: 0.0
Deduct 0 from 6 and we're left with 6.
Take the next digit (6) from the dividend and append it to 6, then repeat: 66 / 386

Step 2:
386 goes into 66 0 times with a remainder of 66.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 66 to get 66.
Bring next digit (9) of the dividend behind the 66 and repeat the process: 669 / 386

Step 3:
The number 386 fits into 669 1 times, leaving a remainder of 283.
Record the quotient 1 as the next digit in the result. 
Result so far: 1.0
Subtracting 386 from 669 leaves us with 283.
Bring next digit (2) of the dividend behind the 283 and repeat the process: 2832 / 386

Step 4:
386 goes into 2832 7 times with a remainder of 130.
Record the quotient 7 as the next digit in the result. 
Result so far: 17.0
Subtracting 2702 from 2832 leaves us with 130.
Grab the next digit (1) from the dividend, add it to 130, then carry on: 1301 / 386

Advancing to step 5:
386 can be fit into 1301 3 times, resulting in a remainder of 143.
The number 3 becomes the next digit in our result. 
Result so far: 173.0
The remainder is 143 after subtracting 1158 from 1301.
Include the next digit (0) from the dividend after 143, then repeat: 1430 / 386

Going ahead to step 6:
386 can be fit into 1430 3 times, resulting in a remainder of 272.
Write down 3 as next digit of the result. 
Result so far: 1733.0
Deduct 1158 from 1430 and we're left with 272.
Fetch the next digit (8) from the dividend, attach it to 272 and continue: 2728 / 386

Going ahead to step 7:
386 goes into 2728 7 times with a remainder of 26.
Use 7 as the next digit of our solution. 
Result so far: 17337.0
The remainder is 26 after subtracting 2702 from 2728.
Include the next digit (2) from the dividend after 26, then repeat: 262 / 386

Moving on to step 8:
386 goes into 262 0 times with a remainder of 262.
Put 0 as the next digit of the answer. 
Result so far: 173370.0
The remainder is 262 after subtracting 0 from 262.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2620, and continue the process.

Let's proceed to step 9:
386 goes into 2620 6 times with a remainder of 304.
The next digit of our result is 6. 
Result so far: 173370.6
If we subtract 2316 from 2620, we get 304.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3040, and continue the process.

Step 10:
The number 386 fits into 3040 7 times, leaving a remainder of 338.
Use 7 as the next digit of our solution. 
Result so far: 173370.67
Deduct 2702 from 3040 and we're left with 338.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3380, and continue the process.

Step 11:
3380 divided by 386 is 8 with a remainder of 292.
The number 8 becomes the next digit in our result. 
Result so far: 173370.678
Subtracting 3088 from 3380 leaves us with 292.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2920, and continue the process.

Step 12:
The number 386 fits into 2920 7 times, leaving a remainder of 218.
Put 7 as the next digit of the answer. 
Result so far: 173370.6787
Deduct 2702 from 2920 and we're left with 218.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2180, and continue the process.

On to step 13:
The number 386 fits into 2180 5 times, leaving a remainder of 250.
The number 5 becomes the next digit in our result. 
Result so far: 173370.67875
If we take 1930 away from 2180, we end up with 250.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2500, and continue the process.

Let's proceed to step 14:
When dividing 2500 by 386, we get 6 with a remainder of 184.
Record the quotient 6 as the next digit in the result. 
Result so far: 173370.678756
Deduct 2316 from 2500 and we're left with 184.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1840, and continue the process.

Let's proceed to step 15:
The number 386 fits into 1840 4 times, leaving a remainder of 296.
The number 4 becomes the next digit in our result. 
Result so far: 173370.6787564
Subtract 1544 from 1840 to get 296.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2960, and continue the process.

Step 16:
If we divide 2960 by 386, we get 7 and a remainder of 258.
Record the quotient 7 as the next digit in the result. 
Result so far: 173370.67875647
If we subtract 2702 from 2960, we get 258.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2580, and continue the process.

In conclusion, the division gives 173370.67875647 with a balance of 2.58e-07.