We look at the division of 55747970 by 645 
The aim is to understand the frequency of 645 in 55747970.

Let's proceed to step 1:
If we divide 5 by 645, we get 0 and a remainder of 5.
Use 0 as the next digit of our solution. 
Result so far: 0.0
The remainder is 5 after subtracting 0 from 5.
Take the next digit (5) from the dividend and append it to 5, then repeat: 55 / 645

Step 2:
If we divide 55 by 645, we get 0 and a remainder of 55.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Deduct 0 from 55 and we're left with 55.
Append the next digit (7) from the dividend to 55 and continue with: 557 / 645

Let's proceed to step 3:
645 can be fit into 557 0 times, resulting in a remainder of 557.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtracting 0 from 557 leaves us with 557.
Grab the next digit (4) from the dividend, add it to 557, then carry on: 5574 / 645

Step 4:
645 goes into 5574 8 times with a remainder of 414.
The next digit of our result is 8. 
Result so far: 8.0
Subtract 5160 from 5574 to get 414.
Grab the next digit (7) from the dividend, add it to 414, then carry on: 4147 / 645

Step 5:
The number 645 fits into 4147 6 times, leaving a remainder of 277.
The next digit of our result is 6. 
Result so far: 86.0
The remainder is 277 after subtracting 3870 from 4147.
Include the next digit (9) from the dividend after 277, then repeat: 2779 / 645

Advancing to step 6:
If we divide 2779 by 645, we get 4 and a remainder of 199.
Record the quotient 4 as the next digit in the result. 
Result so far: 864.0
If we subtract 2580 from 2779, we get 199.
Take the next digit (7) from the dividend and append it to 199, then repeat: 1997 / 645

Going ahead to step 7:
If we divide 1997 by 645, we get 3 and a remainder of 62.
Put 3 as the next digit of the answer. 
Result so far: 8643.0
Deduct 1935 from 1997 and we're left with 62.
Append the next digit (0) from the dividend to 62 and continue with: 620 / 645

Let's proceed to step 8:
The number 645 fits into 620 0 times, leaving a remainder of 620.
Write down 0 as next digit of the result. 
Result so far: 86430.0
Deduct 0 from 620 and we're left with 620.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6200, and continue the process.

Let's proceed to step 9:
If we divide 6200 by 645, we get 9 and a remainder of 395.
The next digit of our result is 9. 
Result so far: 86430.9
Subtracting 5805 from 6200 leaves us with 395.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3950, and continue the process.

Advancing to step 10:
When dividing 3950 by 645, we get 6 with a remainder of 80.
Use 6 as the next digit of our solution. 
Result so far: 86430.96
Deduct 3870 from 3950 and we're left with 80.
Since there are no more digits in the dividend, we add a zero to the remainder making it 800, and continue the process.

Step 11:
If we divide 800 by 645, we get 1 and a remainder of 155.
The number 1 becomes the next digit in our result. 
Result so far: 86430.961
If we take 645 away from 800, we end up with 155.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1550, and continue the process.

Moving on to step 12:
When dividing 1550 by 645, we get 2 with a remainder of 260.
The next digit of our result is 2. 
Result so far: 86430.9612
The remainder is 260 after subtracting 1290 from 1550.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2600, and continue the process.

Step 13:
645 can be fit into 2600 4 times, resulting in a remainder of 20.
The number 4 becomes the next digit in our result. 
Result so far: 86430.96124
Deduct 2580 from 2600 and we're left with 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Let's proceed to step 14:
645 can be fit into 200 0 times, resulting in a remainder of 200.
The number 0 becomes the next digit in our result. 
Result so far: 86430.96124
If we take 0 away from 200, we end up with 200.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2000, and continue the process.

Going ahead to step 15:
645 can be fit into 2000 3 times, resulting in a remainder of 65.
Record the quotient 3 as the next digit in the result. 
Result so far: 86430.9612403
The remainder is 65 after subtracting 1935 from 2000.
Since there are no more digits in the dividend, we add a zero to the remainder making it 650, and continue the process.

Step 16:
650 divided by 645 is 1 with a remainder of 5.
Put 1 as the next digit of the answer. 
Result so far: 86430.96124031
Deduct 645 from 650 and we're left with 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

After the division, we end up with 86430.96124031 and a remainder of 5e-09.