660139 ÷ 75 
We want to figure out the number of times 660139 can be divided by 75.

On to step 1:
When dividing 6 by 75, we get 0 with a remainder of 6.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we take 0 away from 6, we end up with 6.
Grab the next digit (6) from the dividend, add it to 6, then carry on: 66 / 75

Let's proceed to step 2:
The number 75 fits into 66 0 times, leaving a remainder of 66.
Put 0 as the next digit of the answer. 
Result so far: 0.0
The remainder is 66 after subtracting 0 from 66.
Bring next digit (0) of the dividend behind the 66 and repeat the process: 660 / 75

Let's proceed to step 3:
If we divide 660 by 75, we get 8 and a remainder of 60.
Use 8 as the next digit of our solution. 
Result so far: 8.0
Deduct 600 from 660 and we're left with 60.
Include the next digit (1) from the dividend after 60, then repeat: 601 / 75

Advancing to step 4:
When dividing 601 by 75, we get 8 with a remainder of 1.
The next digit of our result is 8. 
Result so far: 88.0
If we subtract 600 from 601, we get 1.
Take the next digit (3) from the dividend and append it to 1, then repeat: 13 / 75

Let's proceed to step 5:
75 can be fit into 13 0 times, resulting in a remainder of 13.
The next digit of our result is 0. 
Result so far: 880.0
If we subtract 0 from 13, we get 13.
Take the next digit (9) from the dividend and append it to 13, then repeat: 139 / 75

Advancing to step 6:
75 goes into 139 1 times with a remainder of 64.
Use 1 as the next digit of our solution. 
Result so far: 8801.0
If we subtract 75 from 139, we get 64.
Since there are no more digits in the dividend, we add a zero to the remainder making it 640, and continue the process.

Step 7:
If we divide 640 by 75, we get 8 and a remainder of 40.
Write down 8 as next digit of the result. 
Result so far: 8801.8
If we take 600 away from 640, we end up with 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

Moving on to step 8:
The number 75 fits into 400 5 times, leaving a remainder of 25.
The next digit of our result is 5. 
Result so far: 8801.85
If we take 375 away from 400, we end up with 25.
Since there are no more digits in the dividend, we add a zero to the remainder making it 250, and continue the process.

Going ahead to step 9:
If we divide 250 by 75, we get 3 and a remainder of 25.
Write down 3 as next digit of the result. 
Result so far: 8801.853
Subtract 225 from 250 to get 25.
Since there are no more digits in the dividend, we add a zero to the remainder making it 250, and continue the process.

Moving on to step 10:
75 goes into 250 3 times with a remainder of 25.
Put 3 as the next digit of the answer. 
Result so far: 8801.8533
If we subtract 225 from 250, we get 25.
Since there are no more digits in the dividend, we add a zero to the remainder making it 250, and continue the process.

The final outcome is 8801.8533, with a leftover of 0.00025.