We look at the division of 890134 by 21 
We want to divide 890134 by 21.

On to step 1:
The number 21 fits into 8 0 times, leaving a remainder of 8.
The next digit of our result is 0. 
Result so far: 0.0
If we subtract 0 from 8, we get 8.
Append the next digit (9) from the dividend to 8 and continue with: 89 / 21

Advancing to step 2:
If we divide 89 by 21, we get 4 and a remainder of 5.
Write down 4 as next digit of the result. 
Result so far: 4.0
Subtracting 84 from 89 leaves us with 5.
Append the next digit (0) from the dividend to 5 and continue with: 50 / 21

Moving on to step 3:
When dividing 50 by 21, we get 2 with a remainder of 8.
Record the quotient 2 as the next digit in the result. 
Result so far: 42.0
If we take 42 away from 50, we end up with 8.
Bring next digit (1) of the dividend behind the 8 and repeat the process: 81 / 21

Step 4:
If we divide 81 by 21, we get 3 and a remainder of 18.
Put 3 as the next digit of the answer. 
Result so far: 423.0
Subtract 63 from 81 to get 18.
Bring next digit (3) of the dividend behind the 18 and repeat the process: 183 / 21

Moving on to step 5:
The number 21 fits into 183 8 times, leaving a remainder of 15.
Record the quotient 8 as the next digit in the result. 
Result so far: 4238.0
If we subtract 168 from 183, we get 15.
Include the next digit (4) from the dividend after 15, then repeat: 154 / 21

Moving on to step 6:
21 goes into 154 7 times with a remainder of 7.
The number 7 becomes the next digit in our result. 
Result so far: 42387.0
If we take 147 away from 154, we end up with 7.
Since there are no more digits in the dividend, we add a zero to the remainder making it 70, and continue the process.

Advancing to step 7:
When dividing 70 by 21, we get 3 with a remainder of 7.
Record the quotient 3 as the next digit in the result. 
Result so far: 42387.3
If we subtract 63 from 70, we get 7.
Since there are no more digits in the dividend, we add a zero to the remainder making it 70, and continue the process.

Going ahead to step 8:
If we divide 70 by 21, we get 3 and a remainder of 7.
Put 3 as the next digit of the answer. 
Result so far: 42387.33
The remainder is 7 after subtracting 63 from 70.
Since there are no more digits in the dividend, we add a zero to the remainder making it 70, and continue the process.

After the division, we end up with 42387.33 and a remainder of 0.007.