The waiting time W for a certain unusual phenomenon is described by an exponential distribution with mean 18.3 years. What is the probability that the phenomenon will occur during the first 15 years of observation?

Question

The waiting time   W   for a certain unusual phenomenon is described by an exponential distribution with mean   18.3   years.   What is the probability that the phenomenon will occur during the first   15   years of observation?

anonymous · Answer

is "exponential waiting time" a poisson process?

anonymous · Answer

I dont know for sure, one thing i know it is the  Exponential Densities

anonymous · Answer

maybe it is poisson process idk for sure

anonymous · Answer

forget this P(W≤15)

tkhunny · Answer

Have you considered calculating the integral?

$\int_{0}^{15}\dfrac{1}{18.3}e^{-t/18.3}\;dt$

anonymous · Answer

no never come into my mind

anonymous · Answer

I got 0.5594 
thx for the help

tkhunny · Answer

Really?  Neither your text nor your teacher ever mentioned it?  Very odd.

Convince yourself that this is the right distribution by using the limits $(0,\infty)$