We divide 80901993 by 987
The aim is to understand the frequency of 987 in 80901993.

Let's proceed to step 1:
When dividing 8 by 987, we get 0 with a remainder of 8.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtract 0 from 8 to get 8.
Fetch the next digit (0) from the dividend, attach it to 8 and continue: 80 / 987

Moving on to step 2:
When dividing 80 by 987, we get 0 with a remainder of 80.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we subtract 0 from 80, we get 80.
Grab the next digit (9) from the dividend, add it to 80, then carry on: 809 / 987

On to step 3:
When dividing 809 by 987, we get 0 with a remainder of 809.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we take 0 away from 809, we end up with 809.
Grab the next digit (0) from the dividend, add it to 809, then carry on: 8090 / 987

Going ahead to step 4:
987 can be fit into 8090 8 times, resulting in a remainder of 194.
The number 8 becomes the next digit in our result. 
Result so far: 8.0
If we take 7896 away from 8090, we end up with 194.
Take the next digit (1) from the dividend and append it to 194, then repeat: 1941 / 987

Moving on to step 5:
If we divide 1941 by 987, we get 1 and a remainder of 954.
Put 1 as the next digit of the answer. 
Result so far: 81.0
The remainder is 954 after subtracting 987 from 1941.
Include the next digit (9) from the dividend after 954, then repeat: 9549 / 987

On to step 6:
987 can be fit into 9549 9 times, resulting in a remainder of 666.
The next digit of our result is 9. 
Result so far: 819.0
Subtract 8883 from 9549 to get 666.
Append the next digit (9) from the dividend to 666 and continue with: 6669 / 987

Advancing to step 7:
The number 987 fits into 6669 6 times, leaving a remainder of 747.
Record the quotient 6 as the next digit in the result. 
Result so far: 8196.0
The remainder is 747 after subtracting 5922 from 6669.
Append the next digit (3) from the dividend to 747 and continue with: 7473 / 987

Advancing to step 8:
When dividing 7473 by 987, we get 7 with a remainder of 564.
Record the quotient 7 as the next digit in the result. 
Result so far: 81967.0
If we take 6909 away from 7473, we end up with 564.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5640, and continue the process.

Let's proceed to step 9:
If we divide 5640 by 987, we get 5 and a remainder of 705.
The number 5 becomes the next digit in our result. 
Result so far: 81967.5
Deduct 4935 from 5640 and we're left with 705.
Since there are no more digits in the dividend, we add a zero to the remainder making it 7050, and continue the process.

Advancing to step 10:
987 can be fit into 7050 7 times, resulting in a remainder of 141.
Use 7 as the next digit of our solution. 
Result so far: 81967.57
Subtracting 6909 from 7050 leaves us with 141.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1410, and continue the process.

Moving on to step 11:
When dividing 1410 by 987, we get 1 with a remainder of 423.
Use 1 as the next digit of our solution. 
Result so far: 81967.571
The remainder is 423 after subtracting 987 from 1410.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4230, and continue the process.

Let's proceed to step 12:
4230 divided by 987 is 4 with a remainder of 282.
Write down 4 as next digit of the result. 
Result so far: 81967.5714
The remainder is 282 after subtracting 3948 from 4230.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2820, and continue the process.

Advancing to step 13:
If we divide 2820 by 987, we get 2 and a remainder of 846.
Write down 2 as next digit of the result. 
Result so far: 81967.57142
If we subtract 1974 from 2820, we get 846.
Since there are no more digits in the dividend, we add a zero to the remainder making it 8460, and continue the process.

Let's proceed to step 14:
When dividing 8460 by 987, we get 8 with a remainder of 564.
The next digit of our result is 8. 
Result so far: 81967.571428
If we subtract 7896 from 8460, we get 564.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5640, and continue the process.

Moving on to step 15:
987 can be fit into 5640 5 times, resulting in a remainder of 705.
The number 5 becomes the next digit in our result. 
Result so far: 81967.5714285
If we take 4935 away from 5640, we end up with 705.
Since there are no more digits in the dividend, we add a zero to the remainder making it 7050, and continue the process.

Advancing to step 16:
If we divide 7050 by 987, we get 7 and a remainder of 141.
Use 7 as the next digit of our solution. 
Result so far: 81967.57142857
The remainder is 141 after subtracting 6909 from 7050.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1410, and continue the process.

The final result is 81967.57142857 with a remainder of 1.41e-07.