Outside a home, there is a 9-key keypad numbered 1 through 9. The correct five-digit code will open the garage door. The numbers can be repeated in the code.
The probability that the correct code is given on the first try, assuming that the owner doesn't remember it is
There are 9 possible numbers (1,2,3,4,5,6,7,8,9) that can be placed in 5 places.
N= 9^5 = 59049
1/59049 = 0.00169350878084%