15758209 ÷ 309 
We want to figure out the number of times 15758209 can be divided by 309.

On to step 1:
When dividing 1 by 309, we get 0 with a remainder of 1.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtract 0 from 1 to get 1.
Append the next digit (5) from the dividend to 1 and continue with: 15 / 309

On to step 2:
309 goes into 15 0 times with a remainder of 15.
Put 0 as the next digit of the answer. 
Result so far: 0.0
If we take 0 away from 15, we end up with 15.
Take the next digit (7) from the dividend and append it to 15, then repeat: 157 / 309

Going ahead to step 3:
309 can be fit into 157 0 times, resulting in a remainder of 157.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtract 0 from 157 to get 157.
Grab the next digit (5) from the dividend, add it to 157, then carry on: 1575 / 309

Moving on to step 4:
If we divide 1575 by 309, we get 5 and a remainder of 30.
The number 5 becomes the next digit in our result. 
Result so far: 5.0
Subtract 1545 from 1575 to get 30.
Take the next digit (8) from the dividend and append it to 30, then repeat: 308 / 309

Let's proceed to step 5:
When dividing 308 by 309, we get 0 with a remainder of 308.
Use 0 as the next digit of our solution. 
Result so far: 50.0
Subtract 0 from 308 to get 308.
Bring next digit (2) of the dividend behind the 308 and repeat the process: 3082 / 309

Moving on to step 6:
309 goes into 3082 9 times with a remainder of 301.
Write down 9 as next digit of the result. 
Result so far: 509.0
The remainder is 301 after subtracting 2781 from 3082.
Grab the next digit (0) from the dividend, add it to 301, then carry on: 3010 / 309

Moving on to step 7:
309 can be fit into 3010 9 times, resulting in a remainder of 229.
The number 9 becomes the next digit in our result. 
Result so far: 5099.0
Subtract 2781 from 3010 to get 229.
Include the next digit (9) from the dividend after 229, then repeat: 2299 / 309

Moving on to step 8:
If we divide 2299 by 309, we get 7 and a remainder of 136.
The next digit of our result is 7. 
Result so far: 50997.0
Subtracting 2163 from 2299 leaves us with 136.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1360, and continue the process.

Moving on to step 9:
309 goes into 1360 4 times with a remainder of 124.
Use 4 as the next digit of our solution. 
Result so far: 50997.4
If we take 1236 away from 1360, we end up with 124.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1240, and continue the process.

On to step 10:
If we divide 1240 by 309, we get 4 and a remainder of 4.
Write down 4 as next digit of the result. 
Result so far: 50997.44
If we subtract 1236 from 1240, we get 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Our division results in 50997.44 with a remaining 0.004.