Suppose that the time a machine can operate before breaking down is exponentially distributed with a mean of 10 hours. If the machine has already been operating for 2 hours, what is the probability that it will last another 2 hours?
my try is ==> P(2< x <4) = P(X<4) - P(X<2)
my output is 0.1484 which is incorrect , any help as I am fresh learner?