We look at the division of 77173493 by 45 
The aim is to understand the frequency of 45 in 77173493.

Advancing to step 1:
7 divided by 45 is 0 with a remainder of 7.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
The remainder is 7 after subtracting 0 from 7.
Bring next digit (7) of the dividend behind the 7 and repeat the process: 77 / 45

Step 2:
The number 45 fits into 77 1 times, leaving a remainder of 32.
Put 1 as the next digit of the answer. 
Result so far: 1.0
Subtracting 45 from 77 leaves us with 32.
Take the next digit (1) from the dividend and append it to 32, then repeat: 321 / 45

Let's proceed to step 3:
45 can be fit into 321 7 times, resulting in a remainder of 6.
The next digit of our result is 7. 
Result so far: 17.0
The remainder is 6 after subtracting 315 from 321.
Append the next digit (7) from the dividend to 6 and continue with: 67 / 45

Let's proceed to step 4:
When dividing 67 by 45, we get 1 with a remainder of 22.
Use 1 as the next digit of our solution. 
Result so far: 171.0
If we subtract 45 from 67, we get 22.
Bring next digit (3) of the dividend behind the 22 and repeat the process: 223 / 45

Advancing to step 5:
When dividing 223 by 45, we get 4 with a remainder of 43.
Put 4 as the next digit of the answer. 
Result so far: 1714.0
Subtracting 180 from 223 leaves us with 43.
Grab the next digit (4) from the dividend, add it to 43, then carry on: 434 / 45

Advancing to step 6:
434 divided by 45 is 9 with a remainder of 29.
Record the quotient 9 as the next digit in the result. 
Result so far: 17149.0
Deduct 405 from 434 and we're left with 29.
Append the next digit (9) from the dividend to 29 and continue with: 299 / 45

Step 7:
299 divided by 45 is 6 with a remainder of 29.
Put 6 as the next digit of the answer. 
Result so far: 171496.0
Subtract 270 from 299 to get 29.
Fetch the next digit (3) from the dividend, attach it to 29 and continue: 293 / 45

Advancing to step 8:
If we divide 293 by 45, we get 6 and a remainder of 23.
Record the quotient 6 as the next digit in the result. 
Result so far: 1714966.0
If we take 270 away from 293, we end up with 23.
Since there are no more digits in the dividend, we add a zero to the remainder making it 230, and continue the process.

Going ahead to step 9:
When dividing 230 by 45, we get 5 with a remainder of 5.
Record the quotient 5 as the next digit in the result. 
Result so far: 1714966.5
Deduct 225 from 230 and we're left with 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Step 10:
45 goes into 50 1 times with a remainder of 5.
Write down 1 as next digit of the result. 
Result so far: 1714966.51
Deduct 45 from 50 and we're left with 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

On to step 11:
If we divide 50 by 45, we get 1 and a remainder of 5.
Use 1 as the next digit of our solution. 
Result so far: 1714966.511
Subtract 45 from 50 to get 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

The quotient of the division is 1714966.511, and the remainder is 0.0005.