91390 ÷ 8 = 11423 R6
Alright, let's work through the division of 91390 by 8 step by step.

Step 1:
8 goes into 9 1 times with a remainder of 1.
Write down 1 as next digit of of the result. 
Result so far: 1
Subtract 8 from 9 to get 1.
Bring next digit (1) of the dividend behind the 1 and repeat the process: 11 / 8

Step 2:
8 goes into 11 1 times with a remainder of 3.
Write down 1 as next digit of of the result. 
Result so far: 11
Subtract 8 from 11 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: 114
Subtract 32 from 33 to get 1.
Bring next digit (9) of the dividend behind the 1 and repeat the process: 19 / 8

Step 4:
8 goes into 19 2 times with a remainder of 3.
Write down 2 as next digit of of the result. 
Result so far: 1142
Subtract 16 from 19 to get 3.
Bring next digit (0) of the dividend behind the 3 and repeat the process: 30 / 8

Step 5:
8 goes into 30 3 times with a remainder of 6.
Write down 3 as next digit of of the result. 
Result so far: 11423
Subtract 24 from 30 to get 6.

The final result is 11423 with a remainder of 6.