Question

Camila sets up a passcode on her tablet, which allows only six-digit codes. She has heard that it's more secure if a digit is repeated in the passcode. A spy sneaks a look at Camila's tablet and sees her fingerprints on the screen over five numbers. What is the probability the spy is able to unlock the tablet on his first try? Express your answer as a fraction in lowest terms or a decimal rounded to the nearest millionth.

Answer 1

Camilar is allowed to set-up a passcode of 6 digit only. According to spy's look, she already used 5 number (distinct) as, Camila has already heard that repitition of digit is Grore secure' while setting a passcode. Suppose Camila! used 5 distinct digit for earlier. 5 digit code As she want to repeat a digit, she will have only I choice out of these 5 digit (which are used earlier ) so to unlock the passcode set by Camilar spy will press

one a key out of those 5 distinct key Probability of unlocking the - posscode by spy key which will used by Camila nous of choices available Hence, able probability to unlock the the spy is passcode is 0.2