990225 ÷ 77 
The aim is to understand the frequency of 77 in 990225.

Advancing to step 1:
When dividing 9 by 77, we get 0 with a remainder of 9.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtracting 0 from 9 leaves us with 9.
Grab the next digit (9) from the dividend, add it to 9, then carry on: 99 / 77

Let's proceed to step 2:
When dividing 99 by 77, we get 1 with a remainder of 22.
Use 1 as the next digit of our solution. 
Result so far: 1.0
If we take 77 away from 99, we end up with 22.
Grab the next digit (0) from the dividend, add it to 22, then carry on: 220 / 77

On to step 3:
The number 77 fits into 220 2 times, leaving a remainder of 66.
Write down 2 as next digit of the result. 
Result so far: 12.0
The remainder is 66 after subtracting 154 from 220.
Bring next digit (2) of the dividend behind the 66 and repeat the process: 662 / 77

Going ahead to step 4:
77 goes into 662 8 times with a remainder of 46.
Use 8 as the next digit of our solution. 
Result so far: 128.0
If we take 616 away from 662, we end up with 46.
Append the next digit (2) from the dividend to 46 and continue with: 462 / 77

Advancing to step 5:
462 divided by 77 is 6 with a remainder of 0.
The number 6 becomes the next digit in our result. 
Result so far: 1286.0
Deduct 462 from 462 and we're left with 0.
Fetch the next digit (5) from the dividend, attach it to 0 and continue: 5 / 77

Going ahead to step 6:
77 can be fit into 5 0 times, resulting in a remainder of 5.
The number 0 becomes the next digit in our result. 
Result so far: 12860.0
If we take 0 away from 5, we end up 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.

Going ahead to step 7:
When dividing 50 by 77, we get 0 with a remainder of 50.
The number 0 becomes the next digit in our result. 
Result so far: 12860.0
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.

Advancing to step 8:
77 goes into 500 6 times with a remainder of 38.
Use 6 as the next digit of our solution. 
Result so far: 12860.06
The remainder is 38 after subtracting 462 from 500.
Since there are no more digits in the dividend, we add a zero to the remainder making it 380, and continue the process.

Advancing to step 9:
When dividing 380 by 77, we get 4 with a remainder of 72.
Use 4 as the next digit of our solution. 
Result so far: 12860.064
If we subtract 308 from 380, we get 72.
Since there are no more digits in the dividend, we add a zero to the remainder making it 720, and continue the process.

Moving on to step 10:
If we divide 720 by 77, we get 9 and a remainder of 27.
Record the quotient 9 as the next digit in the result. 
Result so far: 12860.0649
The remainder is 27 after subtracting 693 from 720.
Since there are no more digits in the dividend, we add a zero to the remainder making it 270, and continue the process.

On to step 11:
77 can be fit into 270 3 times, resulting in a remainder of 39.
Put 3 as the next digit of the answer. 
Result so far: 12860.06493
If we take 231 away from 270, we end up with 39.
Since there are no more digits in the dividend, we add a zero to the remainder making it 390, and continue the process.

Moving on to step 12:
390 divided by 77 is 5 with a remainder of 5.
The next digit of our result is 5. 
Result so far: 12860.064935
Subtracting 385 from 390 leaves us 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 13:
50 divided by 77 is 0 with a remainder of 50.
Use 0 as the next digit of our solution. 
Result so far: 12860.064935
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.

Advancing to step 14:
If we divide 500 by 77, we get 6 and a remainder of 38.
Record the quotient 6 as the next digit in the result. 
Result so far: 12860.06493506
The remainder is 38 after subtracting 462 from 500.
Since there are no more digits in the dividend, we add a zero to the remainder making it 380, and continue the process.

After the division, we end up with 12860.06493506 and a remainder of 3.8e-08.