We look at the division of 96637320 by 991 
The aim is to understand the frequency of 991 in 96637320.

Step 1:
If we divide 9 by 991, we get 0 and a remainder of 9.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Deduct 0 from 9 and we're left with 9.
Bring next digit (6) of the dividend behind the 9 and repeat the process: 96 / 991

Moving on to step 2:
991 can be fit into 96 0 times, resulting in a remainder of 96.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 96 to get 96.
Fetch the next digit (6) from the dividend, attach it to 96 and continue: 966 / 991

On to step 3:
If we divide 966 by 991, we get 0 and a remainder of 966.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Deduct 0 from 966 and we're left with 966.
Append the next digit (3) from the dividend to 966 and continue with: 9663 / 991

Advancing to step 4:
991 can be fit into 9663 9 times, resulting in a remainder of 744.
Use 9 as the next digit of our solution. 
Result so far: 9.0
If we subtract 8919 from 9663, we get 744.
Take the next digit (7) from the dividend and append it to 744, then repeat: 7447 / 991

Moving on to step 5:
The number 991 fits into 7447 7 times, leaving a remainder of 510.
The number 7 becomes the next digit in our result. 
Result so far: 97.0
Deduct 6937 from 7447 and we're left with 510.
Fetch the next digit (3) from the dividend, attach it to 510 and continue: 5103 / 991

Step 6:
When dividing 5103 by 991, we get 5 with a remainder of 148.
The number 5 becomes the next digit in our result. 
Result so far: 975.0
Subtract 4955 from 5103 to get 148.
Grab the next digit (2) from the dividend, add it to 148, then carry on: 1482 / 991

Step 7:
991 can be fit into 1482 1 times, resulting in a remainder of 491.
Use 1 as the next digit of our solution. 
Result so far: 9751.0
If we subtract 991 from 1482, we get 491.
Fetch the next digit (0) from the dividend, attach it to 491 and continue: 4910 / 991

Moving on to step 8:
991 can be fit into 4910 4 times, resulting in a remainder of 946.
The number 4 becomes the next digit in our result. 
Result so far: 97514.0
If we take 3964 away from 4910, we end up with 946.
Since there are no more digits in the dividend, we add a zero to the remainder making it 9460, and continue the process.

Advancing to step 9:
If we divide 9460 by 991, we get 9 and a remainder of 541.
Write down 9 as next digit of the result. 
Result so far: 97514.9
If we take 8919 away from 9460, we end up with 541.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5410, and continue the process.

Moving on to step 10:
The number 991 fits into 5410 5 times, leaving a remainder of 455.
Put 5 as the next digit of the answer. 
Result so far: 97514.95
Subtracting 4955 from 5410 leaves us with 455.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4550, and continue the process.

Going ahead to step 11:
991 can be fit into 4550 4 times, resulting in a remainder of 586.
Write down 4 as next digit of the result. 
Result so far: 97514.954
If we take 3964 away from 4550, we end up with 586.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5860, and continue the process.

Step 12:
When dividing 5860 by 991, we get 5 with a remainder of 905.
Record the quotient 5 as the next digit in the result. 
Result so far: 97514.9545
Deduct 4955 from 5860 and we're left with 905.
Since there are no more digits in the dividend, we add a zero to the remainder making it 9050, and continue the process.

On to step 13:
If we divide 9050 by 991, we get 9 and a remainder of 131.
The number 9 becomes the next digit in our result. 
Result so far: 97514.95459
If we subtract 8919 from 9050, we get 131.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1310, and continue the process.

Advancing to step 14:
When dividing 1310 by 991, we get 1 with a remainder of 319.
Record the quotient 1 as the next digit in the result. 
Result so far: 97514.954591
Deduct 991 from 1310 and we're left with 319.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3190, and continue the process.

Going ahead to step 15:
If we divide 3190 by 991, we get 3 and a remainder of 217.
The next digit of our result is 3. 
Result so far: 97514.9545913
Subtract 2973 from 3190 to get 217.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2170, and continue the process.

Going ahead to step 16:
2170 divided by 991 is 2 with a remainder of 188.
The next digit of our result is 2. 
Result so far: 97514.95459132
If we subtract 1982 from 2170, we get 188.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1880, and continue the process.

After the division, we end up with 97514.95459132 and a remainder of 1.88e-07.