We're dividing 66412180 by 345 
The aim is to understand the frequency of 345 in 66412180.

Going ahead to step 1:
The number 345 fits into 6 0 times, leaving a remainder of 6.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
The remainder is 6 after subtracting 0 from 6.
Grab the next digit (6) from the dividend, add it to 6, then carry on: 66 / 345

Moving on to step 2:
The number 345 fits into 66 0 times, leaving a remainder of 66.
Put 0 as the next digit of the answer. 
Result so far: 0.0
If we subtract 0 from 66, we get 66.
Grab the next digit (4) from the dividend, add it to 66, then carry on: 664 / 345

On to step 3:
If we divide 664 by 345, we get 1 and a remainder of 319.
Record the quotient 1 as the next digit in the result. 
Result so far: 1.0
If we subtract 345 from 664, we get 319.
Include the next digit (1) from the dividend after 319, then repeat: 3191 / 345

Moving on to step 4:
345 goes into 3191 9 times with a remainder of 86.
The next digit of our result is 9. 
Result so far: 19.0
Subtracting 3105 from 3191 leaves us with 86.
Take the next digit (2) from the dividend and append it to 86, then repeat: 862 / 345

Advancing to step 5:
345 can be fit into 862 2 times, resulting in a remainder of 172.
The number 2 becomes the next digit in our result. 
Result so far: 192.0
The remainder is 172 after subtracting 690 from 862.
Take the next digit (1) from the dividend and append it to 172, then repeat: 1721 / 345

Moving on to step 6:
The number 345 fits into 1721 4 times, leaving a remainder of 341.
Use 4 as the next digit of our solution. 
Result so far: 1924.0
If we take 1380 away from 1721, we end up with 341.
Take the next digit (8) from the dividend and append it to 341, then repeat: 3418 / 345

Let's proceed to step 7:
When dividing 3418 by 345, we get 9 with a remainder of 313.
The next digit of our result is 9. 
Result so far: 19249.0
Subtract 3105 from 3418 to get 313.
Bring next digit (0) of the dividend behind the 313 and repeat the process: 3130 / 345

Step 8:
The number 345 fits into 3130 9 times, leaving a remainder of 25.
Record the quotient 9 as the next digit in the result. 
Result so far: 192499.0
The remainder is 25 after subtracting 3105 from 3130.
Since there are no more digits in the dividend, we add a zero to the remainder making it 250, and continue the process.

Moving on to step 9:
345 goes into 250 0 times with a remainder of 250.
Record the quotient 0 as the next digit in the result. 
Result so far: 192499.0
If we subtract 0 from 250, we get 250.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2500, and continue the process.

Moving on to step 10:
345 goes into 2500 7 times with a remainder of 85.
Put 7 as the next digit of the answer. 
Result so far: 192499.07
The remainder is 85 after subtracting 2415 from 2500.
Since there are no more digits in the dividend, we add a zero to the remainder making it 850, and continue the process.

On to step 11:
The number 345 fits into 850 2 times, leaving a remainder of 160.
Write down 2 as next digit of the result. 
Result so far: 192499.072
Deduct 690 from 850 and we're left with 160.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1600, and continue the process.

On to step 12:
345 goes into 1600 4 times with a remainder of 220.
The number 4 becomes the next digit in our result. 
Result so far: 192499.0724
Subtract 1380 from 1600 to get 220.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2200, and continue the process.

Advancing to step 13:
The number 345 fits into 2200 6 times, leaving a remainder of 130.
The number 6 becomes the next digit in our result. 
Result so far: 192499.07246
Subtracting 2070 from 2200 leaves us with 130.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1300, and continue the process.

Advancing to step 14:
If we divide 1300 by 345, we get 3 and a remainder of 265.
Use 3 as the next digit of our solution. 
Result so far: 192499.072463
The remainder is 265 after subtracting 1035 from 1300.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2650, and continue the process.

Step 15:
When dividing 2650 by 345, we get 7 with a remainder of 235.
The next digit of our result is 7. 
Result so far: 192499.0724637
If we subtract 2415 from 2650, we get 235.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2350, and continue the process.

Let's proceed to step 16:
345 can be fit into 2350 6 times, resulting in a remainder of 280.
Record the quotient 6 as the next digit in the result. 
Result so far: 192499.07246376
If we subtract 2070 from 2350, we get 280.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2800, and continue the process.

The final result is 192499.07246376 with a remainder of 2.8e-07.