We're dividing 139991 by 70 
The aim is to understand the frequency of 70 in 139991.

Let's proceed to step 1:
70 goes into 1 0 times with a remainder of 1.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtracting 0 from 1 leaves us with 1.
Include the next digit (3) from the dividend after 1, then repeat: 13 / 70

Advancing to step 2:
70 can be fit into 13 0 times, resulting in a remainder of 13.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Deduct 0 from 13 and we're left with 13.
Bring next digit (9) of the dividend behind the 13 and repeat the process: 139 / 70

Moving on to step 3:
When dividing 139 by 70, we get 1 with a remainder of 69.
The number 1 becomes the next digit in our result. 
Result so far: 1.0
Subtract 70 from 139 to get 69.
Bring next digit (9) of the dividend behind the 69 and repeat the process: 699 / 70

Advancing to step 4:
699 divided by 70 is 9 with a remainder of 69.
The next digit of our result is 9. 
Result so far: 19.0
If we take 630 away from 699, we end up with 69.
Grab the next digit (9) from the dividend, add it to 69, then carry on: 699 / 70

Moving on to step 5:
The number 70 fits into 699 9 times, leaving a remainder of 69.
Record the quotient 9 as the next digit in the result. 
Result so far: 199.0
Deduct 630 from 699 and we're left with 69.
Fetch the next digit (1) from the dividend, attach it to 69 and continue: 691 / 70

Advancing to step 6:
When dividing 691 by 70, we get 9 with a remainder of 61.
Record the quotient 9 as the next digit in the result. 
Result so far: 1999.0
If we subtract 630 from 691, we get 61.
Since there are no more digits in the dividend, we add a zero to the remainder making it 610, and continue the process.

Advancing to step 7:
610 divided by 70 is 8 with a remainder of 50.
Record the quotient 8 as the next digit in the result. 
Result so far: 1999.8
If we take 560 away from 610, 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.

Moving on to step 8:
70 can be fit into 500 7 times, resulting in a remainder of 10.
Put 7 as the next digit of the answer. 
Result so far: 1999.87
Subtracting 490 from 500 leaves us with 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Step 9:
70 goes into 100 1 times with a remainder of 30.
Use 1 as the next digit of our solution. 
Result so far: 1999.871
Deduct 70 from 100 and we're left with 30.
Since there are no more digits in the dividend, we add a zero to the remainder making it 300, and continue the process.

Advancing to step 10:
300 divided by 70 is 4 with a remainder of 20.
Write down 4 as next digit of the result. 
Result so far: 1999.8714
Subtract 280 from 300 to get 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Let's proceed to step 11:
The number 70 fits into 200 2 times, leaving a remainder of 60.
Record the quotient 2 as the next digit in the result. 
Result so far: 1999.87142
If we subtract 140 from 200, we get 60.
Since there are no more digits in the dividend, we add a zero to the remainder making it 600, and continue the process.

Step 12:
70 can be fit into 600 8 times, resulting in a remainder of 40.
Put 8 as the next digit of the answer. 
Result so far: 1999.871428
The remainder is 40 after subtracting 560 from 600.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

Going ahead to step 13:
The number 70 fits into 400 5 times, leaving a remainder of 50.
Put 5 as the next digit of the answer. 
Result so far: 1999.8714285
If we subtract 350 from 400, we get 50.
Since there are no more digits in the dividend, we add a zero to the remainder making it 500, and continue the process.

On to step 14:
70 goes into 500 7 times with a remainder of 10.
The number 7 becomes the next digit in our result. 
Result so far: 1999.87142857
If we subtract 490 from 500, we get 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

The final outcome is 1999.87142857, with a leftover of 1e-08.