Let's divide 42169991 by 40
We're looking to find how many times 40 goes into 42169991.

Moving on to step 1:
The number 40 fits into 4 0 times, leaving a remainder of 4.
The next digit of our result is 0. 
Result so far: 0.0
Deduct 0 from 4 and we're left with 4.
Bring next digit (2) of the dividend behind the 4 and repeat the process: 42 / 40

Advancing to step 2:
40 goes into 42 1 times with a remainder of 2.
Put 1 as the next digit of the answer. 
Result so far: 1.0
Subtract 40 from 42 to get 2.
Include the next digit (1) from the dividend after 2, then repeat: 21 / 40

Moving on to step 3:
The number 40 fits into 21 0 times, leaving a remainder of 21.
Use 0 as the next digit of our solution. 
Result so far: 10.0
If we subtract 0 from 21, we get 21.
Take the next digit (6) from the dividend and append it to 21, then repeat: 216 / 40

Advancing to step 4:
The number 40 fits into 216 5 times, leaving a remainder of 16.
The next digit of our result is 5. 
Result so far: 105.0
If we subtract 200 from 216, we get 16.
Take the next digit (9) from the dividend and append it to 16, then repeat: 169 / 40

Step 5:
The number 40 fits into 169 4 times, leaving a remainder of 9.
Use 4 as the next digit of our solution. 
Result so far: 1054.0
If we take 160 away from 169, we end up with 9.
Grab the next digit (9) from the dividend, add it to 9, then carry on: 99 / 40

Going ahead to step 6:
When dividing 99 by 40, we get 2 with a remainder of 19.
Use 2 as the next digit of our solution. 
Result so far: 10542.0
Subtract 80 from 99 to get 19.
Take the next digit (9) from the dividend and append it to 19, then repeat: 199 / 40

Advancing to step 7:
When dividing 199 by 40, we get 4 with a remainder of 39.
Put 4 as the next digit of the answer. 
Result so far: 105424.0
If we take 160 away from 199, we end up with 39.
Grab the next digit (1) from the dividend, add it to 39, then carry on: 391 / 40

Let's proceed to step 8:
If we divide 391 by 40, we get 9 and a remainder of 31.
Write down 9 as next digit of the result. 
Result so far: 1054249.0
Subtracting 360 from 391 leaves us with 31.
Since there are no more digits in the dividend, we add a zero to the remainder making it 310, and continue the process.

Going ahead to step 9:
40 can be fit into 310 7 times, resulting in a remainder of 30.
The number 7 becomes the next digit in our result. 
Result so far: 1054249.7
Subtracting 280 from 310 leaves us with 30.
Since there are no more digits in the dividend, we add a zero to the remainder making it 300, and continue the process.

Let's proceed to step 10:
The number 40 fits into 300 7 times, leaving a remainder of 20.
The next digit of our result is 7. 
Result so far: 1054249.77
The remainder is 20 after subtracting 280 from 300.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

The final result is 1054249.77 with a remainder of 0.02.