According to the timetable the London coach is due to arrive at 2pm however because of the variable traffic conditions the coach is likely to be late. let T denote the actual arrival time and X (in minutes) be T-2pm

X is a random variable with pdf = lamda*e^(-lamda(x-w))

where w and lamda are two given constants

find the probability that the coach is late - so does this mean P(X>0) and how do i calculate this?

also if the coach has not arrived by 2pm what is the probability that the coach arrives in the next 10 mins? is this P(0<x<10