642581 divided by 90 
We're looking to find how many times 90 goes into 642581.

Step 1:
6 divided by 90 is 0 with a remainder of 6.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we subtract 0 from 6, we get 6.
Fetch the next digit (4) from the dividend, attach it to 6 and continue: 64 / 90

Advancing to step 2:
When dividing 64 by 90, we get 0 with a remainder of 64.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtracting 0 from 64 leaves us with 64.
Append the next digit (2) from the dividend to 64 and continue with: 642 / 90

Let's proceed to step 3:
90 goes into 642 7 times with a remainder of 12.
The number 7 becomes the next digit in our result. 
Result so far: 7.0
The remainder is 12 after subtracting 630 from 642.
Include the next digit (5) from the dividend after 12, then repeat: 125 / 90

Going ahead to step 4:
When dividing 125 by 90, we get 1 with a remainder of 35.
The next digit of our result is 1. 
Result so far: 71.0
The remainder is 35 after subtracting 90 from 125.
Include the next digit (8) from the dividend after 35, then repeat: 358 / 90

On to step 5:
When dividing 358 by 90, we get 3 with a remainder of 88.
The number 3 becomes the next digit in our result. 
Result so far: 713.0
Deduct 270 from 358 and we're left with 88.
Fetch the next digit (1) from the dividend, attach it to 88 and continue: 881 / 90

On to step 6:
If we divide 881 by 90, we get 9 and a remainder of 71.
Put 9 as the next digit of the answer. 
Result so far: 7139.0
If we take 810 away from 881, we end up with 71.
Since there are no more digits in the dividend, we add a zero to the remainder making it 710, and continue the process.

Advancing to step 7:
When dividing 710 by 90, we get 7 with a remainder of 80.
Record the quotient 7 as the next digit in the result. 
Result so far: 7139.7
The remainder is 80 after subtracting 630 from 710.
Since there are no more digits in the dividend, we add a zero to the remainder making it 800, and continue the process.

Going ahead to step 8:
When dividing 800 by 90, we get 8 with a remainder of 80.
The number 8 becomes the next digit in our result. 
Result so far: 7139.78
Deduct 720 from 800 and we're left with 80.
Since there are no more digits in the dividend, we add a zero to the remainder making it 800, and continue the process.

Step 9:
If we divide 800 by 90, we get 8 and a remainder of 80.
Put 8 as the next digit of the answer. 
Result so far: 7139.788
The remainder is 80 after subtracting 720 from 800.
Since there are no more digits in the dividend, we add a zero to the remainder making it 800, and continue the process.

The final outcome is 7139.788, with a leftover of 0.008.