161872 ÷ 42 
We want to divide 161872 by 42.

Step 1:
When dividing 1 by 42, we get 0 with a remainder of 1.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we take 0 away from 1, we end up with 1.
Grab the next digit (6) from the dividend, add it to 1, then carry on: 16 / 42

Moving on to step 2:
When dividing 16 by 42, we get 0 with a remainder of 16.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
The remainder is 16 after subtracting 0 from 16.
Fetch the next digit (1) from the dividend, attach it to 16 and continue: 161 / 42

On to step 3:
The number 42 fits into 161 3 times, leaving a remainder of 35.
Record the quotient 3 as the next digit in the result. 
Result so far: 3.0
Subtract 126 from 161 to get 35.
Grab the next digit (8) from the dividend, add it to 35, then carry on: 358 / 42

Step 4:
If we divide 358 by 42, we get 8 and a remainder of 22.
Write down 8 as next digit of the result. 
Result so far: 38.0
Subtracting 336 from 358 leaves us with 22.
Include the next digit (7) from the dividend after 22, then repeat: 227 / 42

Advancing to step 5:
When dividing 227 by 42, we get 5 with a remainder of 17.
Write down 5 as next digit of the result. 
Result so far: 385.0
Subtract 210 from 227 to get 17.
Bring next digit (2) of the dividend behind the 17 and repeat the process: 172 / 42

Advancing to step 6:
42 can be fit into 172 4 times, resulting in a remainder of 4.
Use 4 as the next digit of our solution. 
Result so far: 3854.0
The remainder is 4 after subtracting 168 from 172.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Step 7:
42 goes into 40 0 times with a remainder of 40.
The next digit of our result is 0. 
Result so far: 3854.0
The remainder is 40 after subtracting 0 from 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

On to step 8:
42 goes into 400 9 times with a remainder of 22.
Use 9 as the next digit of our solution. 
Result so far: 3854.09
If we take 378 away from 400, we end up with 22.
Since there are no more digits in the dividend, we add a zero to the remainder making it 220, and continue the process.

Advancing to step 9:
When dividing 220 by 42, we get 5 with a remainder of 10.
Write down 5 as next digit of the result. 
Result so far: 3854.095
Subtracting 210 from 220 leaves us with 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Going ahead to step 10:
42 can be fit into 100 2 times, resulting in a remainder of 16.
Record the quotient 2 as the next digit in the result. 
Result so far: 3854.0952
Subtract 84 from 100 to get 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

Let's proceed to step 11:
When dividing 160 by 42, we get 3 with a remainder of 34.
The number 3 becomes the next digit in our result. 
Result so far: 3854.09523
If we subtract 126 from 160, we get 34.
Since there are no more digits in the dividend, we add a zero to the remainder making it 340, and continue the process.

Let's proceed to step 12:
340 divided by 42 is 8 with a remainder of 4.
Record the quotient 8 as the next digit in the result. 
Result so far: 3854.095238
Subtracting 336 from 340 leaves us with 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Moving on to step 13:
If we divide 40 by 42, we get 0 and a remainder of 40.
Write down 0 as next digit of the result. 
Result so far: 3854.095238
If we take 0 away from 40, we end up with 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

Step 14:
42 can be fit into 400 9 times, resulting in a remainder of 22.
The next digit of our result is 9. 
Result so far: 3854.09523809
Subtracting 378 from 400 leaves us with 22.
Since there are no more digits in the dividend, we add a zero to the remainder making it 220, and continue the process.

The final outcome is 3854.09523809, with a leftover of 2.2e-08.