We're dividing 78021251 by 456 
The aim is to understand the frequency of 456 in 78021251.

Advancing to step 1:
7 divided by 456 is 0 with a remainder of 7.
The next digit of our result is 0. 
Result so far: 0.0
If we subtract 0 from 7, we get 7.
Append the next digit (8) from the dividend to 7 and continue with: 78 / 456

Advancing to step 2:
The number 456 fits into 78 0 times, leaving a remainder of 78.
Put 0 as the next digit of the answer. 
Result so far: 0.0
The remainder is 78 after subtracting 0 from 78.
Take the next digit (0) from the dividend and append it to 78, then repeat: 780 / 456

On to step 3:
When dividing 780 by 456, we get 1 with a remainder of 324.
Put 1 as the next digit of the answer. 
Result so far: 1.0
The remainder is 324 after subtracting 456 from 780.
Take the next digit (2) from the dividend and append it to 324, then repeat: 3242 / 456

Let's proceed to step 4:
456 goes into 3242 7 times with a remainder of 50.
The next digit of our result is 7. 
Result so far: 17.0
Subtract 3192 from 3242 to get 50.
Fetch the next digit (1) from the dividend, attach it to 50 and continue: 501 / 456

Going ahead to step 5:
456 can be fit into 501 1 times, resulting in a remainder of 45.
The next digit of our result is 1. 
Result so far: 171.0
If we subtract 456 from 501, we get 45.
Append the next digit (2) from the dividend to 45 and continue with: 452 / 456

On to step 6:
452 divided by 456 is 0 with a remainder of 452.
The next digit of our result is 0. 
Result so far: 1710.0
The remainder is 452 after subtracting 0 from 452.
Grab the next digit (5) from the dividend, add it to 452, then carry on: 4525 / 456

Moving on to step 7:
4525 divided by 456 is 9 with a remainder of 421.
The number 9 becomes the next digit in our result. 
Result so far: 17109.0
If we subtract 4104 from 4525, we get 421.
Take the next digit (1) from the dividend and append it to 421, then repeat: 4211 / 456

Moving on to step 8:
456 goes into 4211 9 times with a remainder of 107.
Put 9 as the next digit of the answer. 
Result so far: 171099.0
Subtract 4104 from 4211 to get 107.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1070, and continue the process.

Advancing to step 9:
The number 456 fits into 1070 2 times, leaving a remainder of 158.
The next digit of our result is 2. 
Result so far: 171099.2
Subtract 912 from 1070 to get 158.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1580, and continue the process.

Going ahead to step 10:
The number 456 fits into 1580 3 times, leaving a remainder of 212.
Put 3 as the next digit of the answer. 
Result so far: 171099.23
The remainder is 212 after subtracting 1368 from 1580.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2120, and continue the process.

On to step 11:
2120 divided by 456 is 4 with a remainder of 296.
Use 4 as the next digit of our solution. 
Result so far: 171099.234
The remainder is 296 after subtracting 1824 from 2120.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2960, and continue the process.

Let's proceed to step 12:
2960 divided by 456 is 6 with a remainder of 224.
The number 6 becomes the next digit in our result. 
Result so far: 171099.2346
Subtracting 2736 from 2960 leaves us with 224.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2240, and continue the process.

Advancing to step 13:
When dividing 2240 by 456, we get 4 with a remainder of 416.
Use 4 as the next digit of our solution. 
Result so far: 171099.23464
If we take 1824 away from 2240, we end up with 416.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4160, and continue the process.

Let's proceed to step 14:
If we divide 4160 by 456, we get 9 and a remainder of 56.
The number 9 becomes the next digit in our result. 
Result so far: 171099.234649
Subtract 4104 from 4160 to get 56.
Since there are no more digits in the dividend, we add a zero to the remainder making it 560, and continue the process.

Moving on to step 15:
If we divide 560 by 456, we get 1 and a remainder of 104.
Use 1 as the next digit of our solution. 
Result so far: 171099.2346491
Deduct 456 from 560 and we're left with 104.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1040, and continue the process.

Going ahead to step 16:
The number 456 fits into 1040 2 times, leaving a remainder of 128.
Write down 2 as next digit of the result. 
Result so far: 171099.23464912
Deduct 912 from 1040 and we're left with 128.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1280, and continue the process.

After the division, we end up with 171099.23464912 and a remainder of 1.28e-07.