Let's divide 21351355 by 918
We're looking to find how many times 918 goes into 21351355.

Going ahead to step 1:
If we divide 2 by 918, we get 0 and a remainder of 2.
Write down 0 as next digit of the result. 
Result so far: 0.0
The remainder is 2 after subtracting 0 from 2.
Include the next digit (1) from the dividend after 2, then repeat: 21 / 918

On to step 2:
The number 918 fits into 21 0 times, leaving a remainder of 21.
Write down 0 as next digit of the result. 
Result so far: 0.0
Deduct 0 from 21 and we're left with 21.
Take the next digit (3) from the dividend and append it to 21, then repeat: 213 / 918

Moving on to step 3:
When dividing 213 by 918, we get 0 with a remainder of 213.
Put 0 as the next digit of the answer. 
Result so far: 0.0
If we subtract 0 from 213, we get 213.
Append the next digit (5) from the dividend to 213 and continue with: 2135 / 918

Going ahead to step 4:
When dividing 2135 by 918, we get 2 with a remainder of 299.
The next digit of our result is 2. 
Result so far: 2.0
Deduct 1836 from 2135 and we're left with 299.
Include the next digit (1) from the dividend after 299, then repeat: 2991 / 918

On to step 5:
918 can be fit into 2991 3 times, resulting in a remainder of 237.
The number 3 becomes the next digit in our result. 
Result so far: 23.0
Subtracting 2754 from 2991 leaves us with 237.
Append the next digit (3) from the dividend to 237 and continue with: 2373 / 918

Step 6:
If we divide 2373 by 918, we get 2 and a remainder of 537.
Write down 2 as next digit of the result. 
Result so far: 232.0
If we take 1836 away from 2373, we end up with 537.
Take the next digit (5) from the dividend and append it to 537, then repeat: 5375 / 918

Advancing to step 7:
If we divide 5375 by 918, we get 5 and a remainder of 785.
Write down 5 as next digit of the result. 
Result so far: 2325.0
If we take 4590 away from 5375, we end up with 785.
Bring next digit (5) of the dividend behind the 785 and repeat the process: 7855 / 918

Moving on to step 8:
7855 divided by 918 is 8 with a remainder of 511.
Put 8 as the next digit of the answer. 
Result so far: 23258.0
Deduct 7344 from 7855 and we're left with 511.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5110, and continue the process.

On to step 9:
The number 918 fits into 5110 5 times, leaving a remainder of 520.
Use 5 as the next digit of our solution. 
Result so far: 23258.5
The remainder is 520 after subtracting 4590 from 5110.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5200, and continue the process.

Going ahead to step 10:
If we divide 5200 by 918, we get 5 and a remainder of 610.
Put 5 as the next digit of the answer. 
Result so far: 23258.55
Subtracting 4590 from 5200 leaves us with 610.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6100, and continue the process.

After the division, we end up with 23258.55 and a remainder of 0.61.