We divide 644800 by 67
The aim is to understand the frequency of 67 in 644800.

Step 1:
If we divide 6 by 67, we get 0 and a remainder of 6.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Deduct 0 from 6 and we're left with 6.
Grab the next digit (4) from the dividend, add it to 6, then carry on: 64 / 67

Step 2:
67 can be fit into 64 0 times, resulting in a remainder of 64.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtracting 0 from 64 leaves us with 64.
Grab the next digit (4) from the dividend, add it to 64, then carry on: 644 / 67

Going ahead to step 3:
67 goes into 644 9 times with a remainder of 41.
The number 9 becomes the next digit in our result. 
Result so far: 9.0
Subtract 603 from 644 to get 41.
Bring next digit (8) of the dividend behind the 41 and repeat the process: 418 / 67

Going ahead to step 4:
67 can be fit into 418 6 times, resulting in a remainder of 16.
Put 6 as the next digit of the answer. 
Result so far: 96.0
If we subtract 402 from 418, we get 16.
Take the next digit (0) from the dividend and append it to 16, then repeat: 160 / 67

Advancing to step 5:
If we divide 160 by 67, we get 2 and a remainder of 26.
Put 2 as the next digit of the answer. 
Result so far: 962.0
Subtracting 134 from 160 leaves us with 26.
Grab the next digit (0) from the dividend, add it to 26, then carry on: 260 / 67

Going ahead to step 6:
The number 67 fits into 260 3 times, leaving a remainder of 59.
The number 3 becomes the next digit in our result. 
Result so far: 9623.0
Subtract 201 from 260 to get 59.
Since there are no more digits in the dividend, we add a zero to the remainder making it 590, and continue the process.

Step 7:
If we divide 590 by 67, we get 8 and a remainder of 54.
Put 8 as the next digit of the answer. 
Result so far: 9623.8
If we take 536 away from 590, we end up with 54.
Since there are no more digits in the dividend, we add a zero to the remainder making it 540, and continue the process.

Going ahead to step 8:
540 divided by 67 is 8 with a remainder of 4.
The next digit of our result is 8. 
Result so far: 9623.88
Subtracting 536 from 540 leaves us with 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

The final result is 9623.88 with a remainder of 0.004.