We divide 91094050 by 644
The aim is to understand the frequency of 644 in 91094050.

Step 1:
If we divide 9 by 644, we get 0 and a remainder of 9.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtract 0 from 9 to get 9.
Fetch the next digit (1) from the dividend, attach it to 9 and continue: 91 / 644

Moving on to step 2:
644 can be fit into 91 0 times, resulting in a remainder of 91.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtracting 0 from 91 leaves us with 91.
Fetch the next digit (0) from the dividend, attach it to 91 and continue: 910 / 644

Advancing to step 3:
644 goes into 910 1 times with a remainder of 266.
Use 1 as the next digit of our solution. 
Result so far: 1.0
Subtract 644 from 910 to get 266.
Bring next digit (9) of the dividend behind the 266 and repeat the process: 2669 / 644

On to step 4:
644 goes into 2669 4 times with a remainder of 93.
The next digit of our result is 4. 
Result so far: 14.0
Subtracting 2576 from 2669 leaves us with 93.
Bring next digit (4) of the dividend behind the 93 and repeat the process: 934 / 644

Advancing to step 5:
644 can be fit into 934 1 times, resulting in a remainder of 290.
Record the quotient 1 as the next digit in the result. 
Result so far: 141.0
The remainder is 290 after subtracting 644 from 934.
Fetch the next digit (0) from the dividend, attach it to 290 and continue: 2900 / 644

Moving on to step 6:
644 can be fit into 2900 4 times, resulting in a remainder of 324.
The number 4 becomes the next digit in our result. 
Result so far: 1414.0
If we subtract 2576 from 2900, we get 324.
Include the next digit (5) from the dividend after 324, then repeat: 3245 / 644

Moving on to step 7:
When dividing 3245 by 644, we get 5 with a remainder of 25.
Write down 5 as next digit of the result. 
Result so far: 14145.0
If we take 3220 away from 3245, we end up with 25.
Fetch the next digit (0) from the dividend, attach it to 25 and continue: 250 / 644

Advancing to step 8:
If we divide 250 by 644, we get 0 and a remainder of 250.
Use 0 as the next digit of our solution. 
Result so far: 141450.0
Subtracting 0 from 250 leaves us with 250.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2500, and continue the process.

Let's proceed to step 9:
The number 644 fits into 2500 3 times, leaving a remainder of 568.
Put 3 as the next digit of the answer. 
Result so far: 141450.3
Subtract 1932 from 2500 to get 568.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5680, and continue the process.

Step 10:
If we divide 5680 by 644, we get 8 and a remainder of 528.
The number 8 becomes the next digit in our result. 
Result so far: 141450.38
If we subtract 5152 from 5680, we get 528.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5280, and continue the process.

Step 11:
644 can be fit into 5280 8 times, resulting in a remainder of 128.
Put 8 as the next digit of the answer. 
Result so far: 141450.388
Deduct 5152 from 5280 and we're left with 128.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1280, and continue the process.

After the division, we end up with 141450.388 and a remainder of 0.0128.