70815090 ÷ 870 
Let's see how many times 870 fits into 70815090.

Advancing to step 1:
If we divide 7 by 870, we get 0 and a remainder of 7.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we subtract 0 from 7, we get 7.
Include the next digit (0) from the dividend after 7, then repeat: 70 / 870

On to step 2:
870 goes into 70 0 times with a remainder of 70.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we subtract 0 from 70, we get 70.
Take the next digit (8) from the dividend and append it to 70, then repeat: 708 / 870

Step 3:
If we divide 708 by 870, we get 0 and a remainder of 708.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtract 0 from 708 to get 708.
Grab the next digit (1) from the dividend, add it to 708, then carry on: 7081 / 870

Moving on to step 4:
870 can be fit into 7081 8 times, resulting in a remainder of 121.
Use 8 as the next digit of our solution. 
Result so far: 8.0
Deduct 6960 from 7081 and we're left with 121.
Bring next digit (5) of the dividend behind the 121 and repeat the process: 1215 / 870

Going ahead to step 5:
When dividing 1215 by 870, we get 1 with a remainder of 345.
The number 1 becomes the next digit in our result. 
Result so far: 81.0
Subtract 870 from 1215 to get 345.
Bring next digit (0) of the dividend behind the 345 and repeat the process: 3450 / 870

On to step 6:
870 goes into 3450 3 times with a remainder of 840.
The next digit of our result is 3. 
Result so far: 813.0
Subtracting 2610 from 3450 leaves us with 840.
Take the next digit (9) from the dividend and append it to 840, then repeat: 8409 / 870

Going ahead to step 7:
870 goes into 8409 9 times with a remainder of 579.
The number 9 becomes the next digit in our result. 
Result so far: 8139.0
Subtracting 7830 from 8409 leaves us with 579.
Append the next digit (0) from the dividend to 579 and continue with: 5790 / 870

Going ahead to step 8:
870 goes into 5790 6 times with a remainder of 570.
Use 6 as the next digit of our solution. 
Result so far: 81396.0
Subtract 5220 from 5790 to get 570.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5700, and continue the process.

Step 9:
870 can be fit into 5700 6 times, resulting in a remainder of 480.
Write down 6 as next digit of the result. 
Result so far: 81396.6
Subtracting 5220 from 5700 leaves us with 480.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4800, and continue the process.

Advancing to step 10:
870 can be fit into 4800 5 times, resulting in a remainder of 450.
Put 5 as the next digit of the answer. 
Result so far: 81396.65
The remainder is 450 after subtracting 4350 from 4800.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4500, and continue the process.

Advancing to step 11:
870 can be fit into 4500 5 times, resulting in a remainder of 150.
The next digit of our result is 5. 
Result so far: 81396.655
Subtracting 4350 from 4500 leaves us with 150.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1500, and continue the process.

Our division results in 81396.655 with a remaining 0.015.