51234287 divided by 403 
We want to figure out the number of times 51234287 can be divided by 403.

Going ahead to step 1:
403 goes into 5 0 times with a remainder of 5.
Write down 0 as next digit of the result. 
Result so far: 0.0
Deduct 0 from 5 and we're left with 5.
Append the next digit (1) from the dividend to 5 and continue with: 51 / 403

Let's proceed to step 2:
51 divided by 403 is 0 with a remainder of 51.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we take 0 away from 51, we end up with 51.
Bring next digit (2) of the dividend behind the 51 and repeat the process: 512 / 403

Going ahead to step 3:
403 goes into 512 1 times with a remainder of 109.
The next digit of our result is 1. 
Result so far: 1.0
Subtracting 403 from 512 leaves us with 109.
Fetch the next digit (3) from the dividend, attach it to 109 and continue: 1093 / 403

Advancing to step 4:
When dividing 1093 by 403, we get 2 with a remainder of 287.
Record the quotient 2 as the next digit in the result. 
Result so far: 12.0
If we take 806 away from 1093, we end up with 287.
Take the next digit (4) from the dividend and append it to 287, then repeat: 2874 / 403

On to step 5:
403 can be fit into 2874 7 times, resulting in a remainder of 53.
The next digit of our result is 7. 
Result so far: 127.0
The remainder is 53 after subtracting 2821 from 2874.
Include the next digit (2) from the dividend after 53, then repeat: 532 / 403

Let's proceed to step 6:
403 can be fit into 532 1 times, resulting in a remainder of 129.
Put 1 as the next digit of the answer. 
Result so far: 1271.0
Subtract 403 from 532 to get 129.
Grab the next digit (8) from the dividend, add it to 129, then carry on: 1298 / 403

Let's proceed to step 7:
1298 divided by 403 is 3 with a remainder of 89.
Use 3 as the next digit of our solution. 
Result so far: 12713.0
Deduct 1209 from 1298 and we're left with 89.
Grab the next digit (7) from the dividend, add it to 89, then carry on: 897 / 403

Going ahead to step 8:
897 divided by 403 is 2 with a remainder of 91.
The next digit of our result is 2. 
Result so far: 127132.0
If we subtract 806 from 897, we get 91.
Since there are no more digits in the dividend, we add a zero to the remainder making it 910, and continue the process.

Advancing to step 9:
If we divide 910 by 403, we get 2 and a remainder of 104.
The number 2 becomes the next digit in our result. 
Result so far: 127132.2
Subtract 806 from 910 to get 104.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1040, and continue the process.

Moving on to step 10:
When dividing 1040 by 403, we get 2 with a remainder of 234.
Put 2 as the next digit of the answer. 
Result so far: 127132.22
Subtracting 806 from 1040 leaves us with 234.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2340, and continue the process.

After the division, we end up with 127132.22 and a remainder of 0.234.