Let's divide 123772 by 15
We're looking to find how many times 15 goes into 123772.

Going ahead to step 1:
1 divided by 15 is 0 with a remainder of 1.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we take 0 away from 1, we end up with 1.
Bring next digit (2) of the dividend behind the 1 and repeat the process: 12 / 15

Let's proceed to step 2:
If we divide 12 by 15, we get 0 and a remainder of 12.
The next digit of our result is 0. 
Result so far: 0.0
If we take 0 away from 12, we end up with 12.
Fetch the next digit (3) from the dividend, attach it to 12 and continue: 123 / 15

On to step 3:
If we divide 123 by 15, we get 8 and a remainder of 3.
Record the quotient 8 as the next digit in the result. 
Result so far: 8.0
The remainder is 3 after subtracting 120 from 123.
Take the next digit (7) from the dividend and append it to 3, then repeat: 37 / 15

Step 4:
15 can be fit into 37 2 times, resulting in a remainder of 7.
The next digit of our result is 2. 
Result so far: 82.0
If we take 30 away from 37, we end up with 7.
Fetch the next digit (7) from the dividend, attach it to 7 and continue: 77 / 15

Step 5:
The number 15 fits into 77 5 times, leaving a remainder of 2.
Record the quotient 5 as the next digit in the result. 
Result so far: 825.0
If we subtract 75 from 77, we get 2.
Include the next digit (2) from the dividend after 2, then repeat: 22 / 15

On to step 6:
When dividing 22 by 15, we get 1 with a remainder of 7.
Put 1 as the next digit of the answer. 
Result so far: 8251.0
Subtract 15 from 22 to get 7.
Since there are no more digits in the dividend, we add a zero to the remainder making it 70, and continue the process.

Going ahead to step 7:
15 goes into 70 4 times with a remainder of 10.
The number 4 becomes the next digit in our result. 
Result so far: 8251.4
If we subtract 60 from 70, 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.

On to step 8:
When dividing 100 by 15, we get 6 with a remainder of 10.
The number 6 becomes the next digit in our result. 
Result so far: 8251.46
If we subtract 90 from 100, 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.

On to step 9:
When dividing 100 by 15, we get 6 with a remainder of 10.
The number 6 becomes the next digit in our result. 
Result so far: 8251.466
Deduct 90 from 100 and we're left 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.

The final result is 8251.466 with a remainder of 0.001.