We're dividing 6399425 by 143 
Let's see how many times 143 fits into 6399425.

On to step 1:
If we divide 6 by 143, we get 0 and a remainder of 6.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Deduct 0 from 6 and we're left with 6.
Grab the next digit (3) from the dividend, add it to 6, then carry on: 63 / 143

Going ahead to step 2:
If we divide 63 by 143, we get 0 and a remainder of 63.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtracting 0 from 63 leaves us with 63.
Bring next digit (9) of the dividend behind the 63 and repeat the process: 639 / 143

Advancing to step 3:
143 can be fit into 639 4 times, resulting in a remainder of 67.
The next digit of our result is 4. 
Result so far: 4.0
Subtract 572 from 639 to get 67.
Take the next digit (9) from the dividend and append it to 67, then repeat: 679 / 143

On to step 4:
If we divide 679 by 143, we get 4 and a remainder of 107.
Use 4 as the next digit of our solution. 
Result so far: 44.0
Subtracting 572 from 679 leaves us with 107.
Fetch the next digit (4) from the dividend, attach it to 107 and continue: 1074 / 143

Step 5:
When dividing 1074 by 143, we get 7 with a remainder of 73.
The next digit of our result is 7. 
Result so far: 447.0
The remainder is 73 after subtracting 1001 from 1074.
Take the next digit (2) from the dividend and append it to 73, then repeat: 732 / 143

Moving on to step 6:
143 goes into 732 5 times with a remainder of 17.
Record the quotient 5 as the next digit in the result. 
Result so far: 4475.0
If we take 715 away from 732, we end up with 17.
Include the next digit (5) from the dividend after 17, then repeat: 175 / 143

Advancing to step 7:
The number 143 fits into 175 1 times, leaving a remainder of 32.
Record the quotient 1 as the next digit in the result. 
Result so far: 44751.0
Subtracting 143 from 175 leaves us with 32.
Since there are no more digits in the dividend, we add a zero to the remainder making it 320, and continue the process.

Going ahead to step 8:
143 can be fit into 320 2 times, resulting in a remainder of 34.
Record the quotient 2 as the next digit in the result. 
Result so far: 44751.2
If we take 286 away from 320, we end up with 34.
Since there are no more digits in the dividend, we add a zero to the remainder making it 340, and continue the process.

On to step 9:
When dividing 340 by 143, we get 2 with a remainder of 54.
Write down 2 as next digit of the result. 
Result so far: 44751.22
If we take 286 away from 340, we end up with 54.
Since there are no more digits in the dividend, we add a zero to the remainder making it 540, and continue the process.

Our division results in 44751.22 with a remaining 0.054.