Answer:
Step-by-step explanation:
The exponential distribution is "the probability distribution of the time between events in a Poisson process (a process in which events occur continuously and independently at a constant average rate). It is a particular case of the gamma distribution". The probability density function is given by:
And 0 for other case. Let X the random variable that represent "The number of years a radio functions" and we know that the distribution is given by:
We can assume that the random variable t represent the number of years that the radio is already here. So the interest is find this probability:
We have an important property on the exponential distribution called "Memoryless" property and says this:
Where a represent a shift and t the time of interest.
On this case then
We can use the definition of the density function and find this probability: