We look at the division of 375398 by 66 
The aim is to understand the frequency of 66 in 375398.

Advancing to step 1:
When dividing 3 by 66, we get 0 with a remainder of 3.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
The remainder is 3 after subtracting 0 from 3.
Take the next digit (7) from the dividend and append it to 3, then repeat: 37 / 66

Step 2:
When dividing 37 by 66, we get 0 with a remainder of 37.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we take 0 away from 37, we end up with 37.
Grab the next digit (5) from the dividend, add it to 37, then carry on: 375 / 66

Step 3:
66 goes into 375 5 times with a remainder of 45.
Write down 5 as next digit of the result. 
Result so far: 5.0
Subtract 330 from 375 to get 45.
Bring next digit (3) of the dividend behind the 45 and repeat the process: 453 / 66

Moving on to step 4:
When dividing 453 by 66, we get 6 with a remainder of 57.
Use 6 as the next digit of our solution. 
Result so far: 56.0
If we subtract 396 from 453, we get 57.
Append the next digit (9) from the dividend to 57 and continue with: 579 / 66

Step 5:
66 can be fit into 579 8 times, resulting in a remainder of 51.
Put 8 as the next digit of the answer. 
Result so far: 568.0
The remainder is 51 after subtracting 528 from 579.
Grab the next digit (8) from the dividend, add it to 51, then carry on: 518 / 66

Moving on to step 6:
If we divide 518 by 66, we get 7 and a remainder of 56.
Put 7 as the next digit of the answer. 
Result so far: 5687.0
Subtracting 462 from 518 leaves us with 56.
Since there are no more digits in the dividend, we add a zero to the remainder making it 560, and continue the process.

Going ahead to step 7:
66 can be fit into 560 8 times, resulting in a remainder of 32.
The number 8 becomes the next digit in our result. 
Result so far: 5687.8
Subtracting 528 from 560 leaves us with 32.
Since there are no more digits in the dividend, we add a zero to the remainder making it 320, and continue the process.

Let's proceed to step 8:
If we divide 320 by 66, we get 4 and a remainder of 56.
Use 4 as the next digit of our solution. 
Result so far: 5687.84
If we subtract 264 from 320, we get 56.
Since there are no more digits in the dividend, we add a zero to the remainder making it 560, and continue the process.

Advancing to step 9:
560 divided by 66 is 8 with a remainder of 32.
The number 8 becomes the next digit in our result. 
Result so far: 5687.848
Subtract 528 from 560 to get 32.
Since there are no more digits in the dividend, we add a zero to the remainder making it 320, and continue the process.

Let's proceed to step 10:
If we divide 320 by 66, we get 4 and a remainder of 56.
Write down 4 as next digit of the result. 
Result so far: 5687.8484
If we take 264 away from 320, we end up with 56.
Since there are no more digits in the dividend, we add a zero to the remainder making it 560, and continue the process.

Advancing to step 11:
66 can be fit into 560 8 times, resulting in a remainder of 32.
The number 8 becomes the next digit in our result. 
Result so far: 5687.84848
Subtract 528 from 560 to get 32.
Since there are no more digits in the dividend, we add a zero to the remainder making it 320, and continue the process.

Moving on to step 12:
The number 66 fits into 320 4 times, leaving a remainder of 56.
Write down 4 as next digit of the result. 
Result so far: 5687.848484
Subtracting 264 from 320 leaves us with 56.
Since there are no more digits in the dividend, we add a zero to the remainder making it 560, and continue the process.

Moving on to step 13:
66 goes into 560 8 times with a remainder of 32.
The number 8 becomes the next digit in our result. 
Result so far: 5687.8484848
If we take 528 away from 560, we end up with 32.
Since there are no more digits in the dividend, we add a zero to the remainder making it 320, and continue the process.

On to step 14:
The number 66 fits into 320 4 times, leaving a remainder of 56.
Use 4 as the next digit of our solution. 
Result so far: 5687.84848484
The remainder is 56 after subtracting 264 from 320.
Since there are no more digits in the dividend, we add a zero to the remainder making it 560, and continue the process.

In conclusion, the division gives 5687.84848484 with a balance of 5.6e-08.