Stanley’s bicycle lock has 4 dials, each with digits from 0 to 9. What is the probability that someone could guess his combination on the first try by randomly selecting a number from 0 to 9 four times?
(the answer i got was 1/6561)
The number of digits on each dial is 10 and they are independent of each
other (mutually exclusive) so the number of different combinations is ....
==> 10 x 10 x 10 x 10 = 10,000
So, the probability of guessing the combination is 1 / 10,000 = 0.0001