We look at the division of 51168763 by 661 
The aim is to understand the frequency of 661 in 51168763.

Step 1:
5 divided by 661 is 0 with a remainder of 5.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we subtract 0 from 5, we get 5.
Take the next digit (1) from the dividend and append it to 5, then repeat: 51 / 661

Going ahead to step 2:
If we divide 51 by 661, we get 0 and a remainder of 51.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we subtract 0 from 51, we get 51.
Bring next digit (1) of the dividend behind the 51 and repeat the process: 511 / 661

Advancing to step 3:
The number 661 fits into 511 0 times, leaving a remainder of 511.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we subtract 0 from 511, we get 511.
Bring next digit (6) of the dividend behind the 511 and repeat the process: 5116 / 661

Going ahead to step 4:
661 goes into 5116 7 times with a remainder of 489.
The next digit of our result is 7. 
Result so far: 7.0
Deduct 4627 from 5116 and we're left with 489.
Take the next digit (8) from the dividend and append it to 489, then repeat: 4898 / 661

Moving on to step 5:
When dividing 4898 by 661, we get 7 with a remainder of 271.
Use 7 as the next digit of our solution. 
Result so far: 77.0
The remainder is 271 after subtracting 4627 from 4898.
Take the next digit (7) from the dividend and append it to 271, then repeat: 2717 / 661

Advancing to step 6:
2717 divided by 661 is 4 with a remainder of 73.
The next digit of our result is 4. 
Result so far: 774.0
Subtract 2644 from 2717 to get 73.
Include the next digit (6) from the dividend after 73, then repeat: 736 / 661

Step 7:
736 divided by 661 is 1 with a remainder of 75.
The next digit of our result is 1. 
Result so far: 7741.0
If we take 661 away from 736, we end up with 75.
Fetch the next digit (3) from the dividend, attach it to 75 and continue: 753 / 661

Moving on to step 8:
The number 661 fits into 753 1 times, leaving a remainder of 92.
Put 1 as the next digit of the answer. 
Result so far: 77411.0
The remainder is 92 after subtracting 661 from 753.
Since there are no more digits in the dividend, we add a zero to the remainder making it 920, and continue the process.

Going ahead to step 9:
If we divide 920 by 661, we get 1 and a remainder of 259.
Put 1 as the next digit of the answer. 
Result so far: 77411.1
Subtracting 661 from 920 leaves us with 259.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2590, and continue the process.

Advancing to step 10:
When dividing 2590 by 661, we get 3 with a remainder of 607.
Record the quotient 3 as the next digit in the result. 
Result so far: 77411.13
Subtract 1983 from 2590 to get 607.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6070, and continue the process.

On to step 11:
The number 661 fits into 6070 9 times, leaving a remainder of 121.
Put 9 as the next digit of the answer. 
Result so far: 77411.139
Subtract 5949 from 6070 to get 121.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1210, and continue the process.

Advancing to step 12:
661 goes into 1210 1 times with a remainder of 549.
The number 1 becomes the next digit in our result. 
Result so far: 77411.1391
Subtract 661 from 1210 to get 549.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5490, and continue the process.

Step 13:
661 can be fit into 5490 8 times, resulting in a remainder of 202.
Write down 8 as next digit of the result. 
Result so far: 77411.13918
If we subtract 5288 from 5490, we get 202.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2020, and continue the process.

Let's proceed to step 14:
The number 661 fits into 2020 3 times, leaving a remainder of 37.
Use 3 as the next digit of our solution. 
Result so far: 77411.139183
The remainder is 37 after subtracting 1983 from 2020.
Since there are no more digits in the dividend, we add a zero to the remainder making it 370, and continue the process.

Step 15:
The number 661 fits into 370 0 times, leaving a remainder of 370.
Use 0 as the next digit of our solution. 
Result so far: 77411.139183
If we subtract 0 from 370, we get 370.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3700, and continue the process.

Advancing to step 16:
The number 661 fits into 3700 5 times, leaving a remainder of 395.
Write down 5 as next digit of the result. 
Result so far: 77411.13918305
Subtract 3305 from 3700 to get 395.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3950, and continue the process.

Our division results in 77411.13918305 with a remaining 3.95e-07.