We divide 646456 by 45
The aim is to understand the frequency of 45 in 646456.

Step 1:
When dividing 6 by 45, we get 0 with a remainder of 6.
The next digit of our result is 0. 
Result so far: 0.0
Subtract 0 from 6 to get 6.
Fetch the next digit (4) from the dividend, attach it to 6 and continue: 64 / 45

Step 2:
64 divided by 45 is 1 with a remainder of 19.
Put 1 as the next digit of the answer. 
Result so far: 1.0
Deduct 45 from 64 and we're left with 19.
Fetch the next digit (6) from the dividend, attach it to 19 and continue: 196 / 45

Going ahead to step 3:
When dividing 196 by 45, we get 4 with a remainder of 16.
Put 4 as the next digit of the answer. 
Result so far: 14.0
If we take 180 away from 196, we end up with 16.
Take the next digit (4) from the dividend and append it to 16, then repeat: 164 / 45

Step 4:
When dividing 164 by 45, we get 3 with a remainder of 29.
Record the quotient 3 as the next digit in the result. 
Result so far: 143.0
Subtracting 135 from 164 leaves us with 29.
Append the next digit (5) from the dividend to 29 and continue with: 295 / 45

Advancing to step 5:
When dividing 295 by 45, we get 6 with a remainder of 25.
Use 6 as the next digit of our solution. 
Result so far: 1436.0
If we take 270 away from 295, we end up with 25.
Include the next digit (6) from the dividend after 25, then repeat: 256 / 45

Moving on to step 6:
If we divide 256 by 45, we get 5 and a remainder of 31.
The next digit of our result is 5. 
Result so far: 14365.0
The remainder is 31 after subtracting 225 from 256.
Since there are no more digits in the dividend, we add a zero to the remainder making it 310, and continue the process.

On to step 7:
The number 45 fits into 310 6 times, leaving a remainder of 40.
The next digit of our result is 6. 
Result so far: 14365.6
The remainder is 40 after subtracting 270 from 310.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

Moving on to step 8:
400 divided by 45 is 8 with a remainder of 40.
Record the quotient 8 as the next digit in the result. 
Result so far: 14365.68
Subtracting 360 from 400 leaves us with 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

On to step 9:
The number 45 fits into 400 8 times, leaving a remainder of 40.
The next digit of our result is 8. 
Result so far: 14365.688
If we take 360 away from 400, we end up with 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

After the division, we end up with 14365.688 and a remainder of 0.004.