71497121 ÷ 145 
The aim is to understand the frequency of 145 in 71497121.

Step 1:
When dividing 7 by 145, we get 0 with a remainder of 7.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtract 0 from 7 to get 7.
Include the next digit (1) from the dividend after 7, then repeat: 71 / 145

Going ahead to step 2:
145 can be fit into 71 0 times, resulting in a remainder of 71.
The next digit of our result is 0. 
Result so far: 0.0
Subtract 0 from 71 to get 71.
Append the next digit (4) from the dividend to 71 and continue with: 714 / 145

Step 3:
When dividing 714 by 145, we get 4 with a remainder of 134.
The next digit of our result is 4. 
Result so far: 4.0
Subtract 580 from 714 to get 134.
Include the next digit (9) from the dividend after 134, then repeat: 1349 / 145

Advancing to step 4:
145 can be fit into 1349 9 times, resulting in a remainder of 44.
The next digit of our result is 9. 
Result so far: 49.0
Deduct 1305 from 1349 and we're left with 44.
Grab the next digit (7) from the dividend, add it to 44, then carry on: 447 / 145

On to step 5:
145 goes into 447 3 times with a remainder of 12.
The next digit of our result is 3. 
Result so far: 493.0
If we take 435 away from 447, we end up with 12.
Include the next digit (1) from the dividend after 12, then repeat: 121 / 145

On to step 6:
When dividing 121 by 145, we get 0 with a remainder of 121.
The number 0 becomes the next digit in our result. 
Result so far: 4930.0
If we take 0 away from 121, we end up with 121.
Append the next digit (2) from the dividend to 121 and continue with: 1212 / 145

On to step 7:
If we divide 1212 by 145, we get 8 and a remainder of 52.
The number 8 becomes the next digit in our result. 
Result so far: 49308.0
The remainder is 52 after subtracting 1160 from 1212.
Bring next digit (1) of the dividend behind the 52 and repeat the process: 521 / 145

Advancing to step 8:
If we divide 521 by 145, we get 3 and a remainder of 86.
The next digit of our result is 3. 
Result so far: 493083.0
If we subtract 435 from 521, we get 86.
Since there are no more digits in the dividend, we add a zero to the remainder making it 860, and continue the process.

Advancing to step 9:
The number 145 fits into 860 5 times, leaving a remainder of 135.
The next digit of our result is 5. 
Result so far: 493083.5
The remainder is 135 after subtracting 725 from 860.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1350, and continue the process.

Moving on to step 10:
When dividing 1350 by 145, we get 9 with a remainder of 45.
Record the quotient 9 as the next digit in the result. 
Result so far: 493083.59
Subtracting 1305 from 1350 leaves us with 45.
Since there are no more digits in the dividend, we add a zero to the remainder making it 450, and continue the process.

On to step 11:
145 goes into 450 3 times with a remainder of 15.
Write down 3 as next digit of the result. 
Result so far: 493083.593
Subtract 435 from 450 to get 15.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

Going ahead to step 12:
The number 145 fits into 150 1 times, leaving a remainder of 5.
The number 1 becomes the next digit in our result. 
Result so far: 493083.5931
The remainder is 5 after subtracting 145 from 150.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Step 13:
50 divided by 145 is 0 with a remainder of 50.
Put 0 as the next digit of the answer. 
Result so far: 493083.5931
If we take 0 away from 50, we end up with 50.
Since there are no more digits in the dividend, we add a zero to the remainder making it 500, and continue the process.

Step 14:
If we divide 500 by 145, we get 3 and a remainder of 65.
Record the quotient 3 as the next digit in the result. 
Result so far: 493083.593103
Subtracting 435 from 500 leaves us with 65.
Since there are no more digits in the dividend, we add a zero to the remainder making it 650, and continue the process.

Let's proceed to step 15:
145 goes into 650 4 times with a remainder of 70.
Put 4 as the next digit of the answer. 
Result so far: 493083.5931034
If we take 580 away from 650, we end up with 70.
Since there are no more digits in the dividend, we add a zero to the remainder making it 700, and continue the process.

On to step 16:
The number 145 fits into 700 4 times, leaving a remainder of 120.
Put 4 as the next digit of the answer. 
Result so far: 493083.59310344
Subtracting 580 from 700 leaves us with 120.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1200, and continue the process.

Our division results in 493083.59310344 with a remaining 1.2e-07.