We look at the division of 18566872 by 377 
The aim is to understand the frequency of 377 in 18566872.

On to step 1:
1 divided by 377 is 0 with a remainder of 1.
Put 0 as the next digit of the answer. 
Result so far: 0.0
If we take 0 away from 1, we end up with 1.
Bring next digit (8) of the dividend behind the 1 and repeat the process: 18 / 377

Let's proceed to step 2:
377 can be fit into 18 0 times, resulting in a remainder of 18.
Write down 0 as next digit of the result. 
Result so far: 0.0
The remainder is 18 after subtracting 0 from 18.
Append the next digit (5) from the dividend to 18 and continue with: 185 / 377

Going ahead to step 3:
When dividing 185 by 377, we get 0 with a remainder of 185.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we subtract 0 from 185, we get 185.
Grab the next digit (6) from the dividend, add it to 185, then carry on: 1856 / 377

Advancing to step 4:
If we divide 1856 by 377, we get 4 and a remainder of 348.
The number 4 becomes the next digit in our result. 
Result so far: 4.0
Subtracting 1508 from 1856 leaves us with 348.
Fetch the next digit (6) from the dividend, attach it to 348 and continue: 3486 / 377

Let's proceed to step 5:
3486 divided by 377 is 9 with a remainder of 93.
Put 9 as the next digit of the answer. 
Result so far: 49.0
The remainder is 93 after subtracting 3393 from 3486.
Append the next digit (8) from the dividend to 93 and continue with: 938 / 377

Step 6:
377 can be fit into 938 2 times, resulting in a remainder of 184.
Record the quotient 2 as the next digit in the result. 
Result so far: 492.0
Subtracting 754 from 938 leaves us with 184.
Append the next digit (7) from the dividend to 184 and continue with: 1847 / 377

Advancing to step 7:
1847 divided by 377 is 4 with a remainder of 339.
Use 4 as the next digit of our solution. 
Result so far: 4924.0
Subtract 1508 from 1847 to get 339.
Bring next digit (2) of the dividend behind the 339 and repeat the process: 3392 / 377

Advancing to step 8:
When dividing 3392 by 377, we get 8 with a remainder of 376.
Put 8 as the next digit of the answer. 
Result so far: 49248.0
The remainder is 376 after subtracting 3016 from 3392.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3760, and continue the process.

On to step 9:
377 goes into 3760 9 times with a remainder of 367.
The number 9 becomes the next digit in our result. 
Result so far: 49248.9
Deduct 3393 from 3760 and we're left with 367.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3670, and continue the process.

Step 10:
377 goes into 3670 9 times with a remainder of 277.
The next digit of our result is 9. 
Result so far: 49248.99
If we subtract 3393 from 3670, we get 277.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2770, and continue the process.

The final result is 49248.99 with a remainder of 0.277.