We look at the division of 42425902 by 645 
We want to divide 42425902 by 645.

Step 1:
645 can be fit into 4 0 times, resulting in a remainder of 4.
The next digit of our result is 0. 
Result so far: 0.0
If we take 0 away from 4, we end up with 4.
Append the next digit (2) from the dividend to 4 and continue with: 42 / 645

Step 2:
645 goes into 42 0 times with a remainder of 42.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Deduct 0 from 42 and we're left with 42.
Take the next digit (4) from the dividend and append it to 42, then repeat: 424 / 645

On to step 3:
If we divide 424 by 645, we get 0 and a remainder of 424.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Deduct 0 from 424 and we're left with 424.
Include the next digit (2) from the dividend after 424, then repeat: 4242 / 645

Step 4:
When dividing 4242 by 645, we get 6 with a remainder of 372.
Use 6 as the next digit of our solution. 
Result so far: 6.0
If we take 3870 away from 4242, we end up with 372.
Fetch the next digit (5) from the dividend, attach it to 372 and continue: 3725 / 645

On to step 5:
3725 divided by 645 is 5 with a remainder of 500.
The next digit of our result is 5. 
Result so far: 65.0
The remainder is 500 after subtracting 3225 from 3725.
Take the next digit (9) from the dividend and append it to 500, then repeat: 5009 / 645

Going ahead to step 6:
If we divide 5009 by 645, we get 7 and a remainder of 494.
Write down 7 as next digit of the result. 
Result so far: 657.0
If we subtract 4515 from 5009, we get 494.
Append the next digit (0) from the dividend to 494 and continue with: 4940 / 645

Moving on to step 7:
645 can be fit into 4940 7 times, resulting in a remainder of 425.
The next digit of our result is 7. 
Result so far: 6577.0
Subtract 4515 from 4940 to get 425.
Take the next digit (2) from the dividend and append it to 425, then repeat: 4252 / 645

Step 8:
The number 645 fits into 4252 6 times, leaving a remainder of 382.
Record the quotient 6 as the next digit in the result. 
Result so far: 65776.0
If we subtract 3870 from 4252, we get 382.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3820, and continue the process.

Going ahead to step 9:
645 goes into 3820 5 times with a remainder of 595.
Record the quotient 5 as the next digit in the result. 
Result so far: 65776.5
If we subtract 3225 from 3820, we get 595.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5950, and continue the process.

On to step 10:
5950 divided by 645 is 9 with a remainder of 145.
Use 9 as the next digit of our solution. 
Result so far: 65776.59
Subtract 5805 from 5950 to get 145.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1450, and continue the process.

Going ahead to step 11:
645 can be fit into 1450 2 times, resulting in a remainder of 160.
Write down 2 as next digit of the result. 
Result so far: 65776.592
If we subtract 1290 from 1450, we get 160.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1600, and continue the process.

Moving on to step 12:
645 goes into 1600 2 times with a remainder of 310.
The number 2 becomes the next digit in our result. 
Result so far: 65776.5922
Deduct 1290 from 1600 and we're left with 310.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3100, and continue the process.

The final outcome is 65776.5922, with a leftover of 0.0031.