75309 ÷ 8 = 9413 R5
We're going to perform division on 75309 with 8 as the divisor.

Step 1:
8 goes into 7 0 times with a remainder of 7.
Write down 0 as next digit of of the result. 
Result so far: 0
Subtract 0 from 7 to get 7.
Bring next digit (5) of the dividend behind the 7 and repeat the process: 75 / 8

Step 2:
8 goes into 75 9 times with a remainder of 3.
Write down 9 as next digit of of the result. 
Result so far: 9
Subtract 72 from 75 to get 3.
Bring next digit (3) of the dividend behind the 3 and repeat the process: 33 / 8

Step 3:
8 goes into 33 4 times with a remainder of 1.
Write down 4 as next digit of of the result. 
Result so far: 94
Subtract 32 from 33 to get 1.
Bring next digit (0) of the dividend behind the 1 and repeat the process: 10 / 8

Step 4:
8 goes into 10 1 times with a remainder of 2.
Write down 1 as next digit of of the result. 
Result so far: 941
Subtract 8 from 10 to get 2.
Bring next digit (9) of the dividend behind the 2 and repeat the process: 29 / 8

Step 5:
8 goes into 29 3 times with a remainder of 5.
Write down 3 as next digit of of the result. 
Result so far: 9413
Subtract 24 from 29 to get 5.

The final result is 9413 with a remainder of 5.