The random variable X is exponentially distributed, where X represents the time it takes for a person to choose a birthday gift. If X has an average value of 24 minutes, what is the probability that X is less than 32 minutes? (Do not round until the final step. Round your answer to 3 decimal places.)

Respuesta :

Answer:

The probability that X is less than 32 minutes is 0.736.

Step-by-step explanation:

Given : The random variable X is exponentially distributed, where X represents the time it takes for a person to choose a birthday gift. If X has an average value of 24 minutes.

To find : What is the probability that X is less than 32 minutes?

Solution :

If X has an average value of 24 minutes.

i.e. [tex]\lambda=24[/tex]

The random variable X is exponentially distributed, where X represents the time it takes for a person to choose a birthday gift.

The exponentially function is [tex]\frac{1}{\lambda}e^{-\frac{x}{\lambda}}[/tex]

The function form according to question is

[tex]f(x)=\{\frac{1}{24}e^{-\frac{x}{24}}, x>0\}[/tex]

The probability that X is less than 32 minutes is

[tex]P[x<32]=1-e^{-\frac{32}{24}}[/tex]

[tex]P[x<32]=1-0.26359[/tex]

[tex]P[x<32]=0.736[/tex]

Therefore, the probability that X is less than 32 minutes is 0.736.