645674 divided by 18 
The aim is to understand the frequency of 18 in 645674.

Advancing to step 1:
18 can be fit into 6 0 times, resulting in a remainder of 6.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we subtract 0 from 6, we get 6.
Take the next digit (4) from the dividend and append it to 6, then repeat: 64 / 18

Going ahead to step 2:
If we divide 64 by 18, we get 3 and a remainder of 10.
Put 3 as the next digit of the answer. 
Result so far: 3.0
If we subtract 54 from 64, we get 10.
Bring next digit (5) of the dividend behind the 10 and repeat the process: 105 / 18

Moving on to step 3:
When dividing 105 by 18, we get 5 with a remainder of 15.
The next digit of our result is 5. 
Result so far: 35.0
The remainder is 15 after subtracting 90 from 105.
Append the next digit (6) from the dividend to 15 and continue with: 156 / 18

Going ahead to step 4:
The number 18 fits into 156 8 times, leaving a remainder of 12.
Put 8 as the next digit of the answer. 
Result so far: 358.0
Subtracting 144 from 156 leaves us with 12.
Append the next digit (7) from the dividend to 12 and continue with: 127 / 18

Going ahead to step 5:
18 goes into 127 7 times with a remainder of 1.
Record the quotient 7 as the next digit in the result. 
Result so far: 3587.0
The remainder is 1 after subtracting 126 from 127.
Append the next digit (4) from the dividend to 1 and continue with: 14 / 18

Advancing to step 6:
If we divide 14 by 18, we get 0 and a remainder of 14.
Write down 0 as next digit of the result. 
Result so far: 35870.0
Subtracting 0 from 14 leaves us with 14.
Since there are no more digits in the dividend, we add a zero to the remainder making it 140, and continue the process.

Let's proceed to step 7:
The number 18 fits into 140 7 times, leaving a remainder of 14.
Record the quotient 7 as the next digit in the result. 
Result so far: 35870.7
If we take 126 away from 140, we end up with 14.
Since there are no more digits in the dividend, we add a zero to the remainder making it 140, and continue the process.

Step 8:
18 can be fit into 140 7 times, resulting in a remainder of 14.
The number 7 becomes the next digit in our result. 
Result so far: 35870.77
Deduct 126 from 140 and we're left with 14.
Since there are no more digits in the dividend, we add a zero to the remainder making it 140, and continue the process.

The quotient of the division is 35870.77, and the remainder is 0.014.