We divide 33658851 by 645
The aim is to understand the frequency of 645 in 33658851.

On to step 1:
3 divided by 645 is 0 with a remainder of 3.
Put 0 as the next digit of the answer. 
Result so far: 0.0
If we take 0 away from 3, we end up with 3.
Include the next digit (3) from the dividend after 3, then repeat: 33 / 645

Advancing to step 2:
645 can be fit into 33 0 times, resulting in a remainder of 33.
The next digit of our result is 0. 
Result so far: 0.0
If we subtract 0 from 33, we get 33.
Grab the next digit (6) from the dividend, add it to 33, then carry on: 336 / 645

Step 3:
The number 645 fits into 336 0 times, leaving a remainder of 336.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtracting 0 from 336 leaves us with 336.
Grab the next digit (5) from the dividend, add it to 336, then carry on: 3365 / 645

Step 4:
645 can be fit into 3365 5 times, resulting in a remainder of 140.
Put 5 as the next digit of the answer. 
Result so far: 5.0
Subtract 3225 from 3365 to get 140.
Include the next digit (8) from the dividend after 140, then repeat: 1408 / 645

Advancing to step 5:
When dividing 1408 by 645, we get 2 with a remainder of 118.
The number 2 becomes the next digit in our result. 
Result so far: 52.0
If we take 1290 away from 1408, we end up with 118.
Bring next digit (8) of the dividend behind the 118 and repeat the process: 1188 / 645

Moving on to step 6:
1188 divided by 645 is 1 with a remainder of 543.
Use 1 as the next digit of our solution. 
Result so far: 521.0
The remainder is 543 after subtracting 645 from 1188.
Bring next digit (5) of the dividend behind the 543 and repeat the process: 5435 / 645

Going ahead to step 7:
If we divide 5435 by 645, we get 8 and a remainder of 275.
Put 8 as the next digit of the answer. 
Result so far: 5218.0
Deduct 5160 from 5435 and we're left with 275.
Append the next digit (1) from the dividend to 275 and continue with: 2751 / 645

Moving on to step 8:
If we divide 2751 by 645, we get 4 and a remainder of 171.
Record the quotient 4 as the next digit in the result. 
Result so far: 52184.0
The remainder is 171 after subtracting 2580 from 2751.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1710, and continue the process.

Step 9:
1710 divided by 645 is 2 with a remainder of 420.
Use 2 as the next digit of our solution. 
Result so far: 52184.2
Deduct 1290 from 1710 and we're left with 420.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4200, and continue the process.

Advancing to step 10:
645 can be fit into 4200 6 times, resulting in a remainder of 330.
The next digit of our result is 6. 
Result so far: 52184.26
Deduct 3870 from 4200 and we're left with 330.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3300, and continue the process.

On to step 11:
645 goes into 3300 5 times with a remainder of 75.
Write down 5 as next digit of the result. 
Result so far: 52184.265
Deduct 3225 from 3300 and we're left with 75.
Since there are no more digits in the dividend, we add a zero to the remainder making it 750, and continue the process.

On to step 12:
645 can be fit into 750 1 times, resulting in a remainder of 105.
Record the quotient 1 as the next digit in the result. 
Result so far: 52184.2651
Deduct 645 from 750 and we're left with 105.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1050, and continue the process.

Moving on to step 13:
645 can be fit into 1050 1 times, resulting in a remainder of 405.
Use 1 as the next digit of our solution. 
Result so far: 52184.26511
Deduct 645 from 1050 and we're left with 405.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4050, and continue the process.

Our division results in 52184.26511 with a remaining 0.000405.