15530409 ÷ 45 
The aim is to understand the frequency of 45 in 15530409.

Step 1:
When dividing 1 by 45, we get 0 with a remainder of 1.
The next digit of our result is 0. 
Result so far: 0.0
Deduct 0 from 1 and we're left with 1.
Grab the next digit (5) from the dividend, add it to 1, then carry on: 15 / 45

Going ahead to step 2:
45 can be fit into 15 0 times, resulting in a remainder of 15.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtract 0 from 15 to get 15.
Grab the next digit (5) from the dividend, add it to 15, then carry on: 155 / 45

Going ahead to step 3:
45 can be fit into 155 3 times, resulting in a remainder of 20.
Record the quotient 3 as the next digit in the result. 
Result so far: 3.0
If we take 135 away from 155, we end up with 20.
Bring next digit (3) of the dividend behind the 20 and repeat the process: 203 / 45

Advancing to step 4:
203 divided by 45 is 4 with a remainder of 23.
Put 4 as the next digit of the answer. 
Result so far: 34.0
Subtract 180 from 203 to get 23.
Append the next digit (0) from the dividend to 23 and continue with: 230 / 45

Let's proceed to step 5:
When dividing 230 by 45, we get 5 with a remainder of 5.
Put 5 as the next digit of the answer. 
Result so far: 345.0
Subtracting 225 from 230 leaves us with 5.
Bring next digit (4) of the dividend behind the 5 and repeat the process: 54 / 45

Step 6:
The number 45 fits into 54 1 times, leaving a remainder of 9.
Put 1 as the next digit of the answer. 
Result so far: 3451.0
Deduct 45 from 54 and we're left with 9.
Append the next digit (0) from the dividend to 9 and continue with: 90 / 45

Advancing to step 7:
45 can be fit into 90 2 times, resulting in a remainder of 0.
The number 2 becomes the next digit in our result. 
Result so far: 34512.0
Subtract 90 from 90 to get 0.
Fetch the next digit (9) from the dividend, attach it to 0 and continue: 9 / 45

Advancing to step 8:
45 can be fit into 9 0 times, resulting in a remainder of 9.
Put 0 as the next digit of the answer. 
Result so far: 345120.0
Subtracting 0 from 9 leaves us with 9.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

On to step 9:
The number 45 fits into 90 2 times, leaving a remainder of 0.
Put 2 as the next digit of the answer. 
Result so far: 345120.2
Subtracting 90 from 90 leaves us with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Advancing to step 10:
45 can be fit into 0 0 times, resulting in a remainder of 0.
The next digit of our result is 0. 
Result so far: 345120.2
Subtracting 0 from 0 leaves us with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Let's proceed to step 11:
When dividing 0 by 45, we get 0 with a remainder of 0.
The next digit of our result is 0. 
Result so far: 345120.2
The remainder is 0 after subtracting 0 from 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

After the division, we end up with 345120.2 and a remainder of 0.0.