We're dividing 159428 by 40 
Let's see how many times 40 fits into 159428.

Advancing to step 1:
The number 40 fits into 1 0 times, leaving a remainder of 1.
The next digit of our result is 0. 
Result so far: 0.0
Deduct 0 from 1 and we're left with 1.
Take the next digit (5) from the dividend and append it to 1, then repeat: 15 / 40

Advancing to step 2:
When dividing 15 by 40, we get 0 with a remainder of 15.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
The remainder is 15 after subtracting 0 from 15.
Fetch the next digit (9) from the dividend, attach it to 15 and continue: 159 / 40

Moving on to step 3:
When dividing 159 by 40, we get 3 with a remainder of 39.
Use 3 as the next digit of our solution. 
Result so far: 3.0
Subtract 120 from 159 to get 39.
Bring next digit (4) of the dividend behind the 39 and repeat the process: 394 / 40

On to step 4:
The number 40 fits into 394 9 times, leaving a remainder of 34.
Put 9 as the next digit of the answer. 
Result so far: 39.0
Subtract 360 from 394 to get 34.
Include the next digit (2) from the dividend after 34, then repeat: 342 / 40

Let's proceed to step 5:
If we divide 342 by 40, we get 8 and a remainder of 22.
The number 8 becomes the next digit in our result. 
Result so far: 398.0
If we take 320 away from 342, we end up with 22.
Fetch the next digit (8) from the dividend, attach it to 22 and continue: 228 / 40

On to step 6:
40 goes into 228 5 times with a remainder of 28.
Put 5 as the next digit of the answer. 
Result so far: 3985.0
If we subtract 200 from 228, we get 28.
Since there are no more digits in the dividend, we add a zero to the remainder making it 280, and continue the process.

On to step 7:
280 divided by 40 is 7 with a remainder of 0.
Put 7 as the next digit of the answer. 
Result so far: 3985.7
Subtracting 280 from 280 leaves us 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.

Going ahead to step 8:
40 goes into 0 0 times with a remainder of 0.
Use 0 as the next digit of our solution. 
Result so far: 3985.7
If we subtract 0 from 0, 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.

Going ahead to step 9:
0 divided by 40 is 0 with a remainder of 0.
Put 0 as the next digit of the answer. 
Result so far: 3985.7
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.

Our division results in 3985.7 with a remaining 0.0.