Answer :
Answer:
Step-by-step explanation:
Let X be the time for any customer to call at any time to make reservation in Nite Time Inn.
Given that X is exponential with mean = 4 minutes
We are to find the probability
(a) 3 minutes or less.
=[tex]P(X\leq 3)=1-e^{-3/4} =0.5276[/tex]
(b) 4 minutes or less.
[tex]=P(X\leq 4)\\=1-e^{-4/4} =0.6321[/tex]
(c) 5 minutes or less.
[tex]=P(X\leq 5)\\=1-e^{-5/4} =0.7135[/tex]
(d) longer than 5 minutes.
=1-P(X≤5) = 0.2865