51212590 divided by 198 
Our goal is to divide 51212590 by 198.

Step 1:
5 divided by 198 is 0 with a remainder of 5.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtracting 0 from 5 leaves us with 5.
Take the next digit (1) from the dividend and append it to 5, then repeat: 51 / 198

Advancing to step 2:
The number 198 fits into 51 0 times, leaving a remainder of 51.
The next digit of our result is 0. 
Result so far: 0.0
Subtracting 0 from 51 leaves us with 51.
Grab the next digit (2) from the dividend, add it to 51, then carry on: 512 / 198

Step 3:
The number 198 fits into 512 2 times, leaving a remainder of 116.
Use 2 as the next digit of our solution. 
Result so far: 2.0
If we subtract 396 from 512, we get 116.
Append the next digit (1) from the dividend to 116 and continue with: 1161 / 198

Advancing to step 4:
When dividing 1161 by 198, we get 5 with a remainder of 171.
Put 5 as the next digit of the answer. 
Result so far: 25.0
Subtracting 990 from 1161 leaves us with 171.
Take the next digit (2) from the dividend and append it to 171, then repeat: 1712 / 198

Moving on to step 5:
If we divide 1712 by 198, we get 8 and a remainder of 128.
Put 8 as the next digit of the answer. 
Result so far: 258.0
Subtracting 1584 from 1712 leaves us with 128.
Append the next digit (5) from the dividend to 128 and continue with: 1285 / 198

Advancing to step 6:
When dividing 1285 by 198, we get 6 with a remainder of 97.
Use 6 as the next digit of our solution. 
Result so far: 2586.0
If we subtract 1188 from 1285, we get 97.
Grab the next digit (9) from the dividend, add it to 97, then carry on: 979 / 198

Going ahead to step 7:
The number 198 fits into 979 4 times, leaving a remainder of 187.
The next digit of our result is 4. 
Result so far: 25864.0
Subtracting 792 from 979 leaves us with 187.
Append the next digit (0) from the dividend to 187 and continue with: 1870 / 198

Step 8:
198 can be fit into 1870 9 times, resulting in a remainder of 88.
The next digit of our result is 9. 
Result so far: 258649.0
Deduct 1782 from 1870 and we're left with 88.
Since there are no more digits in the dividend, we add a zero to the remainder making it 880, and continue the process.

On to step 9:
If we divide 880 by 198, we get 4 and a remainder of 88.
Use 4 as the next digit of our solution. 
Result so far: 258649.4
The remainder is 88 after subtracting 792 from 880.
Since there are no more digits in the dividend, we add a zero to the remainder making it 880, and continue the process.

Step 10:
When dividing 880 by 198, we get 4 with a remainder of 88.
The next digit of our result is 4. 
Result so far: 258649.44
Subtract 792 from 880 to get 88.
Since there are no more digits in the dividend, we add a zero to the remainder making it 880, and continue the process.

In conclusion, the division gives 258649.44 with a balance of 0.088.