We're dividing 999951 by 3 
Let's see how many times 3 fits into 999951.

Advancing to step 1:
When dividing 9 by 3, we get 3 with a remainder of 0.
Record the quotient 3 as the next digit in the result. 
Result so far: 3.0
The remainder is 0 after subtracting 9 from 9.
Grab the next digit (9) from the dividend, add it to 0, then carry on: 9 / 3

On to step 2:
3 can be fit into 9 3 times, resulting in a remainder of 0.
Use 3 as the next digit of our solution. 
Result so far: 33.0
The remainder is 0 after subtracting 9 from 9.
Bring next digit (9) of the dividend behind the 0 and repeat the process: 9 / 3

Step 3:
The number 3 fits into 9 3 times, leaving a remainder of 0.
Use 3 as the next digit of our solution. 
Result so far: 333.0
Subtract 9 from 9 to get 0.
Fetch the next digit (9) from the dividend, attach it to 0 and continue: 9 / 3

Let's proceed to step 4:
When dividing 9 by 3, we get 3 with a remainder of 0.
The next digit of our result is 3. 
Result so far: 3333.0
Deduct 9 from 9 and we're left with 0.
Append the next digit (5) from the dividend to 0 and continue with: 5 / 3

Let's proceed to step 5:
When dividing 5 by 3, we get 1 with a remainder of 2.
The number 1 becomes the next digit in our result. 
Result so far: 33331.0
The remainder is 2 after subtracting 3 from 5.
Bring next digit (1) of the dividend behind the 2 and repeat the process: 21 / 3

Let's proceed to step 6:
The number 3 fits into 21 7 times, leaving a remainder of 0.
Put 7 as the next digit of the answer. 
Result so far: 333317.0
Subtract 21 from 21 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.

On to step 7:
3 goes into 0 0 times with a remainder of 0.
Write down 0 as next digit of the result. 
Result so far: 333317.0
If we take 0 away from 0, we end up 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.

Moving on to step 8:
0 divided by 3 is 0 with a remainder of 0.
The number 0 becomes the next digit in our result. 
Result so far: 333317.0
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 outcome is 333317.0, with a leftover of 0.0.