642186 divided by 90 
We want to figure out the number of times 642186 can be divided by 90.

On to step 1:
90 goes into 6 0 times with a remainder of 6.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtract 0 from 6 to get 6.
Bring next digit (4) of the dividend behind the 6 and repeat the process: 64 / 90

Advancing to step 2:
If we divide 64 by 90, we get 0 and a remainder of 64.
The next digit of our result is 0. 
Result so far: 0.0
Subtracting 0 from 64 leaves us with 64.
Fetch the next digit (2) from the dividend, attach it to 64 and continue: 642 / 90

Step 3:
The number 90 fits into 642 7 times, leaving a remainder of 12.
Put 7 as the next digit of the answer. 
Result so far: 7.0
The remainder is 12 after subtracting 630 from 642.
Take the next digit (1) from the dividend and append it to 12, then repeat: 121 / 90

Moving on to step 4:
90 can be fit into 121 1 times, resulting in a remainder of 31.
Use 1 as the next digit of our solution. 
Result so far: 71.0
If we subtract 90 from 121, we get 31.
Bring next digit (8) of the dividend behind the 31 and repeat the process: 318 / 90

On to step 5:
If we divide 318 by 90, we get 3 and a remainder of 48.
The next digit of our result is 3. 
Result so far: 713.0
Subtracting 270 from 318 leaves us with 48.
Include the next digit (6) from the dividend after 48, then repeat: 486 / 90

On to step 6:
If we divide 486 by 90, we get 5 and a remainder of 36.
Put 5 as the next digit of the answer. 
Result so far: 7135.0
Deduct 450 from 486 and we're left with 36.
Since there are no more digits in the dividend, we add a zero to the remainder making it 360, and continue the process.

Let's proceed to step 7:
If we divide 360 by 90, we get 4 and a remainder of 0.
The number 4 becomes the next digit in our result. 
Result so far: 7135.4
The remainder is 0 after subtracting 360 from 360.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Going ahead to step 8:
0 divided by 90 is 0 with a remainder of 0.
Use 0 as the next digit of our solution. 
Result so far: 7135.4
Subtracting 0 from 0 leaves us with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Advancing to step 9:
90 can be fit into 0 0 times, resulting in a remainder of 0.
The next digit of our result is 0. 
Result so far: 7135.4
The remainder is 0 after subtracting 0 from 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

After the division, we end up with 7135.4 and a remainder of 0.0.