171938 divided by 42 
We want to figure out the number of times 171938 can be divided by 42.

Advancing to step 1:
42 goes into 1 0 times with a remainder of 1.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 1 to get 1.
Bring next digit (7) of the dividend behind the 1 and repeat the process: 17 / 42

Going ahead to step 2:
17 divided by 42 is 0 with a remainder of 17.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we take 0 away from 17, we end up with 17.
Take the next digit (1) from the dividend and append it to 17, then repeat: 171 / 42

Step 3:
42 can be fit into 171 4 times, resulting in a remainder of 3.
Write down 4 as next digit of the result. 
Result so far: 4.0
Subtracting 168 from 171 leaves us with 3.
Include the next digit (9) from the dividend after 3, then repeat: 39 / 42

Going ahead to step 4:
When dividing 39 by 42, we get 0 with a remainder of 39.
Record the quotient 0 as the next digit in the result. 
Result so far: 40.0
Subtracting 0 from 39 leaves us with 39.
Append the next digit (3) from the dividend to 39 and continue with: 393 / 42

Going ahead to step 5:
42 goes into 393 9 times with a remainder of 15.
Put 9 as the next digit of the answer. 
Result so far: 409.0
Deduct 378 from 393 and we're left with 15.
Grab the next digit (8) from the dividend, add it to 15, then carry on: 158 / 42

On to step 6:
42 can be fit into 158 3 times, resulting in a remainder of 32.
Use 3 as the next digit of our solution. 
Result so far: 4093.0
If we subtract 126 from 158, we get 32.
Since there are no more digits in the dividend, we add a zero to the remainder making it 320, and continue the process.

Step 7:
When dividing 320 by 42, we get 7 with a remainder of 26.
The number 7 becomes the next digit in our result. 
Result so far: 4093.7
Subtract 294 from 320 to get 26.
Since there are no more digits in the dividend, we add a zero to the remainder making it 260, and continue the process.

On to step 8:
42 goes into 260 6 times with a remainder of 8.
Write down 6 as next digit of the result. 
Result so far: 4093.76
Subtracting 252 from 260 leaves us with 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Let's proceed to step 9:
The number 42 fits into 80 1 times, leaving a remainder of 38.
Write down 1 as next digit of the result. 
Result so far: 4093.761
If we subtract 42 from 80, we get 38.
Since there are no more digits in the dividend, we add a zero to the remainder making it 380, and continue the process.

On to step 10:
380 divided by 42 is 9 with a remainder of 2.
The number 9 becomes the next digit in our result. 
Result so far: 4093.7619
If we take 378 away from 380, we end up with 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

Step 11:
42 goes into 20 0 times with a remainder of 20.
Record the quotient 0 as the next digit in the result. 
Result so far: 4093.7619
Subtract 0 from 20 to get 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Advancing to step 12:
42 can be fit into 200 4 times, resulting in a remainder of 32.
Write down 4 as next digit of the result. 
Result so far: 4093.761904
Subtracting 168 from 200 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.

Advancing to step 13:
42 goes into 320 7 times with a remainder of 26.
The number 7 becomes the next digit in our result. 
Result so far: 4093.7619047
The remainder is 26 after subtracting 294 from 320.
Since there are no more digits in the dividend, we add a zero to the remainder making it 260, and continue the process.

Advancing to step 14:
260 divided by 42 is 6 with a remainder of 8.
Write down 6 as next digit of the result. 
Result so far: 4093.76190476
Deduct 252 from 260 and we're left with 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

The final result is 4093.76190476 with a remainder of 8e-09.