We look at the division of 851487 by 7 
We're looking to find how many times 7 goes into 851487.

Advancing to step 1:
7 can be fit into 8 1 times, resulting in a remainder of 1.
The next digit of our result is 1. 
Result so far: 1.0
Subtract 7 from 8 to get 1.
Fetch the next digit (5) from the dividend, attach it to 1 and continue: 15 / 7

Let's proceed to step 2:
15 divided by 7 is 2 with a remainder of 1.
Use 2 as the next digit of our solution. 
Result so far: 12.0
If we take 14 away from 15, we end up with 1.
Include the next digit (1) from the dividend after 1, then repeat: 11 / 7

Moving on to step 3:
7 goes into 11 1 times with a remainder of 4.
Use 1 as the next digit of our solution. 
Result so far: 121.0
Deduct 7 from 11 and we're left with 4.
Append the next digit (4) from the dividend to 4 and continue with: 44 / 7

Let's proceed to step 4:
44 divided by 7 is 6 with a remainder of 2.
Record the quotient 6 as the next digit in the result. 
Result so far: 1216.0
If we subtract 42 from 44, we get 2.
Fetch the next digit (8) from the dividend, attach it to 2 and continue: 28 / 7

Going ahead to step 5:
The number 7 fits into 28 4 times, leaving a remainder of 0.
Write down 4 as next digit of the result. 
Result so far: 12164.0
The remainder is 0 after subtracting 28 from 28.
Take the next digit (7) from the dividend and append it to 0, then repeat: 7 / 7

On to step 6:
7 can be fit into 7 1 times, resulting in a remainder of 0.
Write down 1 as next digit of the result. 
Result so far: 121641.0
If we subtract 7 from 7, we get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Moving on to step 7:
The number 7 fits into 0 0 times, leaving a remainder of 0.
The number 0 becomes the next digit in our result. 
Result so far: 121641.0
Deduct 0 from 0 and we're left with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

On to step 8:
The number 7 fits into 0 0 times, leaving a remainder of 0.
Write down 0 as next digit of the result. 
Result so far: 121641.0
Subtract 0 from 0 to get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

The final result is 121641.0 with a remainder of 0.0.