91902 ÷ 9 = 10211 R3
Alright, let's work through the division of 91902 by 9 step by step.

Step 1:
9 goes into 9 1 times with a remainder of 0.
Write down 1 as next digit of of the result. 
Result so far: 1
Subtract 9 from 9 to get 0.
Bring next digit (1) of the dividend behind the 0 and repeat the process: 1 / 9

Step 2:
9 goes into 1 0 times with a remainder of 1.
Write down 0 as next digit of of the result. 
Result so far: 10
Subtract 0 from 1 to get 1.
Bring next digit (9) of the dividend behind the 1 and repeat the process: 19 / 9

Step 3:
9 goes into 19 2 times with a remainder of 1.
Write down 2 as next digit of of the result. 
Result so far: 102
Subtract 18 from 19 to get 1.
Bring next digit (0) of the dividend behind the 1 and repeat the process: 10 / 9

Step 4:
9 goes into 10 1 times with a remainder of 1.
Write down 1 as next digit of of the result. 
Result so far: 1021
Subtract 9 from 10 to get 1.
Bring next digit (2) of the dividend behind the 1 and repeat the process: 12 / 9

Step 5:
9 goes into 12 1 times with a remainder of 3.
Write down 1 as next digit of of the result. 
Result so far: 10211
Subtract 9 from 12 to get 3.

The final result is 10211 with a remainder of 3.