Answer:
The probability that 5 messages are received in 1 hour is
![P(5)\approx 0.1755](https://img.qammunity.org/2020/formulas/mathematics/college/5k3nnxtfdm5pq5zsnu3m5f3ewl3ouhdi21.png)
The probability that 10 messages are received in 1.5 hours is
![P(10)\approx 0.0858](https://img.qammunity.org/2020/formulas/mathematics/college/a7zgmye9q0dhol7du5jmich2vu20nvdb7o.png)
The probability that less than 2 messages are received in 1/2 hour is
![P(X<2) \approx 0.2873](https://img.qammunity.org/2020/formulas/mathematics/college/1cnkje66bw7g1p7dda50dr907ycj9be1sq.png)
Explanation:
The probability distribution of a Poisson random variable representing the number of successes occurring in a given time interval or a specified region of space is given by the formula:
where
mean number of successes in the given time interval or region of space.
![e=2.71828](https://img.qammunity.org/2020/formulas/mathematics/college/b00nlcaigxp4o1uizx5p1ig9r1jgiho9ts.png)
a) What is the probability that 5 messages are received in 1 hour?
From the information given we know that
![\mu=5](https://img.qammunity.org/2020/formulas/mathematics/college/u8w29i8t5up2aap232z5sba33n2sdqcm5h.png)
Applying the Poisson random variable formula we get:
![P(5)=(e^(-5)\cdot 5^(5))/(5!)\\P(5)\approx 0.1755](https://img.qammunity.org/2020/formulas/mathematics/college/tnciv4ju0s3bc4nk7zp9dzxgc7cqenem2y.png)
b) What is the probability that 10 messages are received in 1.5 hours?
We know from the information given that in 1 hour, 5 messages are received. In 0.5 hours we received 2.5 messages therefore in 1.5 hours we received 7.5 messages
![\mu=7.5](https://img.qammunity.org/2020/formulas/mathematics/college/4ewah1m116l3upvtr4g72v387pgkwzv6nz.png)
Applying the Poisson random variable formula we get:
![P(10)=(e^(-7.5)\cdot 7.5^(10))/(10!)\\P(10)\approx 0.0858](https://img.qammunity.org/2020/formulas/mathematics/college/57qubi3s7tj53v4vdbng2fmlvsmxh2lzzu.png)
c) What is the probability that less than 2 messages are received in 1/2 hour?
We know from the information given that in 1 hour, 5 messages are received therefore in 0.5 hours we received 2.5 messages
![\mu=2.5](https://img.qammunity.org/2020/formulas/mathematics/college/hi158jpuekexdhgccfbfeo3ie5ku7y6l9t.png)
To find the probability that less than 2 messages are received in 1/2 hour we find the values when
and
because
![P(X<2)=P(0)+P(1)](https://img.qammunity.org/2020/formulas/mathematics/college/ydhl4vl2jzlar40k0rs0l7fvmt4c8oh5sy.png)
Applying the Poisson random variable formula we get:
![P(0)=(e^(-2.5)\cdot 2.5^(0))/(0!)\\P(0)\approx 0.0821](https://img.qammunity.org/2020/formulas/mathematics/college/zpjef6diqjbfqo11yfa49g288xtuoxpttm.png)
![P(1)=(e^(-2.5)\cdot 2.5^(1))/(1!)\\P(1)\approx 0.2052](https://img.qammunity.org/2020/formulas/mathematics/college/gxbdretitmvxsxn00sy9oimwdboqqc92dv.png)
![P(X<2)=P(0)+P(1)\\P(X<2)\approx 0.0821+0.2052\\P(X<2) \approx 0.2873](https://img.qammunity.org/2020/formulas/mathematics/college/ihpebp5erdjktr7vy8xftsg5w4uirrvmrj.png)