We look at the division of 78210546 by 515 
Our goal is to divide 78210546 by 515.

Step 1:
If we divide 7 by 515, we get 0 and a remainder of 7.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Deduct 0 from 7 and we're left with 7.
Grab the next digit (8) from the dividend, add it to 7, then carry on: 78 / 515

Going ahead to step 2:
If we divide 78 by 515, we get 0 and a remainder of 78.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtracting 0 from 78 leaves us with 78.
Grab the next digit (2) from the dividend, add it to 78, then carry on: 782 / 515

Advancing to step 3:
782 divided by 515 is 1 with a remainder of 267.
Use 1 as the next digit of our solution. 
Result so far: 1.0
Deduct 515 from 782 and we're left with 267.
Take the next digit (1) from the dividend and append it to 267, then repeat: 2671 / 515

Moving on to step 4:
515 can be fit into 2671 5 times, resulting in a remainder of 96.
Use 5 as the next digit of our solution. 
Result so far: 15.0
Deduct 2575 from 2671 and we're left with 96.
Append the next digit (0) from the dividend to 96 and continue with: 960 / 515

Moving on to step 5:
The number 515 fits into 960 1 times, leaving a remainder of 445.
Use 1 as the next digit of our solution. 
Result so far: 151.0
Subtracting 515 from 960 leaves us with 445.
Bring next digit (5) of the dividend behind the 445 and repeat the process: 4455 / 515

Let's proceed to step 6:
515 goes into 4455 8 times with a remainder of 335.
Put 8 as the next digit of the answer. 
Result so far: 1518.0
If we take 4120 away from 4455, we end up with 335.
Take the next digit (4) from the dividend and append it to 335, then repeat: 3354 / 515

Advancing to step 7:
515 goes into 3354 6 times with a remainder of 264.
Use 6 as the next digit of our solution. 
Result so far: 15186.0
Deduct 3090 from 3354 and we're left with 264.
Bring next digit (6) of the dividend behind the 264 and repeat the process: 2646 / 515

Moving on to step 8:
When dividing 2646 by 515, we get 5 with a remainder of 71.
Use 5 as the next digit of our solution. 
Result so far: 151865.0
The remainder is 71 after subtracting 2575 from 2646.
Since there are no more digits in the dividend, we add a zero to the remainder making it 710, and continue the process.

Moving on to step 9:
When dividing 710 by 515, we get 1 with a remainder of 195.
The next digit of our result is 1. 
Result so far: 151865.1
Subtract 515 from 710 to get 195.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1950, and continue the process.

Moving on to step 10:
515 can be fit into 1950 3 times, resulting in a remainder of 405.
Record the quotient 3 as the next digit in the result. 
Result so far: 151865.13
Subtract 1545 from 1950 to get 405.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4050, and continue the process.

On to step 11:
4050 divided by 515 is 7 with a remainder of 445.
Use 7 as the next digit of our solution. 
Result so far: 151865.137
Subtracting 3605 from 4050 leaves us with 445.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4450, and continue the process.

Step 12:
515 goes into 4450 8 times with a remainder of 330.
The number 8 becomes the next digit in our result. 
Result so far: 151865.1378
Subtract 4120 from 4450 to get 330.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3300, and continue the process.

Moving on to step 13:
When dividing 3300 by 515, we get 6 with a remainder of 210.
Use 6 as the next digit of our solution. 
Result so far: 151865.13786
If we take 3090 away from 3300, we end up with 210.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2100, and continue the process.

Let's proceed to step 14:
515 goes into 2100 4 times with a remainder of 40.
Use 4 as the next digit of our solution. 
Result so far: 151865.137864
If we take 2060 away from 2100, we end up with 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

Advancing to step 15:
515 goes into 400 0 times with a remainder of 400.
Record the quotient 0 as the next digit in the result. 
Result so far: 151865.137864
If we take 0 away from 400, we end up with 400.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4000, and continue the process.

On to step 16:
If we divide 4000 by 515, we get 7 and a remainder of 395.
The number 7 becomes the next digit in our result. 
Result so far: 151865.13786407
Deduct 3605 from 4000 and we're left with 395.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3950, and continue the process.

The final outcome is 151865.13786407, with a leftover of 3.95e-07.