We're dividing 345309 by 85 
We want to divide 345309 by 85.

Moving on to step 1:
85 goes into 3 0 times with a remainder of 3.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtract 0 from 3 to get 3.
Take the next digit (4) from the dividend and append it to 3, then repeat: 34 / 85

On to step 2:
85 can be fit into 34 0 times, resulting in a remainder of 34.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we subtract 0 from 34, we get 34.
Bring next digit (5) of the dividend behind the 34 and repeat the process: 345 / 85

Advancing to step 3:
345 divided by 85 is 4 with a remainder of 5.
The number 4 becomes the next digit in our result. 
Result so far: 4.0
If we subtract 340 from 345, we get 5.
Append the next digit (3) from the dividend to 5 and continue with: 53 / 85

Moving on to step 4:
When dividing 53 by 85, we get 0 with a remainder of 53.
Use 0 as the next digit of our solution. 
Result so far: 40.0
Deduct 0 from 53 and we're left with 53.
Grab the next digit (0) from the dividend, add it to 53, then carry on: 530 / 85

Advancing to step 5:
The number 85 fits into 530 6 times, leaving a remainder of 20.
Use 6 as the next digit of our solution. 
Result so far: 406.0
Subtracting 510 from 530 leaves us with 20.
Bring next digit (9) of the dividend behind the 20 and repeat the process: 209 / 85

Moving on to step 6:
85 can be fit into 209 2 times, resulting in a remainder of 39.
Put 2 as the next digit of the answer. 
Result so far: 4062.0
Subtract 170 from 209 to get 39.
Since there are no more digits in the dividend, we add a zero to the remainder making it 390, and continue the process.

Let's proceed to step 7:
85 can be fit into 390 4 times, resulting in a remainder of 50.
Record the quotient 4 as the next digit in the result. 
Result so far: 4062.4
Deduct 340 from 390 and we're left with 50.
Since there are no more digits in the dividend, we add a zero to the remainder making it 500, and continue the process.

Step 8:
85 can be fit into 500 5 times, resulting in a remainder of 75.
Put 5 as the next digit of the answer. 
Result so far: 4062.45
If we subtract 425 from 500, we get 75.
Since there are no more digits in the dividend, we add a zero to the remainder making it 750, and continue the process.

Going ahead to step 9:
When dividing 750 by 85, we get 8 with a remainder of 70.
The number 8 becomes the next digit in our result. 
Result so far: 4062.458
The remainder is 70 after subtracting 680 from 750.
Since there are no more digits in the dividend, we add a zero to the remainder making it 700, and continue the process.

Advancing to step 10:
85 can be fit into 700 8 times, resulting in a remainder of 20.
The next digit of our result is 8. 
Result so far: 4062.4588
Deduct 680 from 700 and we're left with 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

The quotient of the division is 4062.4588, and the remainder is 0.0002.