Answer:
a) 50.34% probability that the arrival time between customers will be 7 minutes or less.
b) 24.42% probability that the arrival time between customers will be between 3 and 7 minutes
Step-by-step explanation:
Exponential distribution:
The exponential probability distribution, with mean m, is described by the following equation:
![f(x) = \mu e^{-\mu x}](https://tex.z-dn.net/?f=f%28x%29%20%3D%20%5Cmu%20e%5E%7B-%5Cmu%20x%7D)
In which
is the decay parameter.
The probability that x is lower or equal to a is given by:
![P(X \leq x) = \int\limits^a_0 {f(x)} \, dx](https://tex.z-dn.net/?f=P%28X%20%5Cleq%20x%29%20%3D%20%5Cint%5Climits%5Ea_0%20%7Bf%28x%29%7D%20%5C%2C%20dx)
Which has the following solution:
![P(X \leq x) = 1 - e^{-\mu x}](https://tex.z-dn.net/?f=P%28X%20%5Cleq%20x%29%20%3D%201%20-%20e%5E%7B-%5Cmu%20x%7D)
The probability of finding a value higher than x is:
![P(X > x) = 1 - P(X \leq x) = 1 - (1 - e^{-\mu x}) = e^{-\mu x}](https://tex.z-dn.net/?f=P%28X%20%3E%20x%29%20%3D%201%20-%20P%28X%20%5Cleq%20x%29%20%3D%201%20-%20%281%20-%20e%5E%7B-%5Cmu%20x%7D%29%20%3D%20e%5E%7B-%5Cmu%20x%7D)
Mean of 10 minutes:
This means that ![m = 10, \mu = \frac{1}{10} = 0.1](https://tex.z-dn.net/?f=m%20%3D%2010%2C%20%5Cmu%20%3D%20%5Cfrac%7B1%7D%7B10%7D%20%3D%200.1)
A. What is the probability that the arrival time between customers will be 7 minutes or less?
![P(X \leq x) = 1 - e^{-\mu x}](https://tex.z-dn.net/?f=P%28X%20%5Cleq%20x%29%20%3D%201%20-%20e%5E%7B-%5Cmu%20x%7D)
![P(X \leq 7) = 1 - e^{-0.1*7} = 0.5034](https://tex.z-dn.net/?f=P%28X%20%5Cleq%207%29%20%3D%201%20-%20e%5E%7B-0.1%2A7%7D%20%3D%200.5034)
50.34% probability that the arrival time between customers will be 7 minutes or less.
B. What is the probability that the arrival time between customers will be between 3 and 7 minutes?
![P(3 \leq X \leq 7) = P(X \leq 7) - P(X \leq 3)](https://tex.z-dn.net/?f=P%283%20%5Cleq%20X%20%5Cleq%207%29%20%3D%20P%28X%20%5Cleq%207%29%20-%20P%28X%20%5Cleq%203%29)
![P(X \leq x) = 1 - e^{-\mu x}](https://tex.z-dn.net/?f=P%28X%20%5Cleq%20x%29%20%3D%201%20-%20e%5E%7B-%5Cmu%20x%7D)
![P(X \leq 7) = 1 - e^{-0.1*7} = 0.5034](https://tex.z-dn.net/?f=P%28X%20%5Cleq%207%29%20%3D%201%20-%20e%5E%7B-0.1%2A7%7D%20%3D%200.5034)
![P(X \leq 3) = 1 - e^{-0.1*3} = 0.2592](https://tex.z-dn.net/?f=P%28X%20%5Cleq%203%29%20%3D%201%20-%20e%5E%7B-0.1%2A3%7D%20%3D%200.2592)
![P(3 \leq X \leq 7) = P(X \leq 7) - P(X \leq 3) = 0.5034 - 0.2592 = 0.2442](https://tex.z-dn.net/?f=P%283%20%5Cleq%20X%20%5Cleq%207%29%20%3D%20P%28X%20%5Cleq%207%29%20-%20P%28X%20%5Cleq%203%29%20%3D%200.5034%20-%200.2592%20%3D%200.2442)
24.42% probability that the arrival time between customers will be between 3 and 7 minutes
The first graph is what i would think
You could say 84/2, 126/3, or even 168/4
Use Pythagorean thrm
17^2+10^2=21^2
289+100=441
389≠441
This is not a right triangle
Add all of the hours together than divide by 5 should get 40