Bodytemperatures ofhealthy koalasarenormally distributed with a mean of 35.6°C and a standard deviation of 1.3°C. a.What is the probability that a health koalahas a body temperature lessthan 35.0°C? (1pt)b.Veterinarians at a nature preserve in Australiathought a population of koalas might be infected with a virus, so they chose a random sample of n=30koalas and measured their body temperatures. If they got a sample mean body temperature less than 35.0°C, do you think that this population of koalas is healthy? Why/why not?Be specific.(4pt)c.List a potential confounding variable for this study and briefly how it might have impactedthe results. (2pt)2.

Answer :

Answer:

a

 [tex]P(X  < 35) =  32.3 \%[/tex]

b

[tex]P(\= X  < 35) =  0.6 \%[/tex]

Here the probability of koalas mean temperature being less than 35 °C is very small hence the koalas are not healthy

c

A potential confounding variable for this study is  the population of the koalas because in the first question the population was not taken into account and the probability was  [tex]P(X  < 35) =  32.3 \%[/tex] but when the population was taken into account (i.e  n =  30) the probability became

[tex]P(\= X  < 35) =  0.6 \%[/tex]  

Step-by-step explanation:

From the question we are told that

  The mean is  [tex]\mu =  35.6^oC[/tex]

   The standard deviation is  [tex]s =  1.3^oC[/tex]

   The sample size is  n = 30

Generally the  probability that a health koala has a body temperature less than 35.0°C is mathematically represented as

     [tex]P(X  < 35) =  P(\frac{X  - \mu }{s}  < \frac{35 - 35.6}{1.3} )[/tex]

Here  [tex](\frac{X  - \mu }{s} =  Z (The   \ standardized \  value \  of  \  X )[/tex]

So

    [tex]P(X  < 35) =  P(Z < -0.46)[/tex]

From the z-table  P(Z <  -0.46) =  0.323

So  

    [tex]P(X  < 35) =  0.323 [/tex]

Converting to percentage

      [tex]P(X  < 35) =  0.323  * 100 [/tex]

      [tex]P(X  < 35) =  32.3 \%[/tex]

considering question b

The sample mean is  [tex]\= x =  35[/tex]

Generally the standard error of the mean is mathematically represented as

   [tex]\sigma_{\= x} =  \frac{s}{\sqrt{n} }[/tex]

=>  [tex]\sigma_{\= x} =  \frac{1.3}{\sqrt{30} }[/tex]

=>  [tex]\sigma_{\= x} =  0.2373 [/tex]

Generally the probability of the mean body temperature of koalas being less than 35.0°C is mathematically represented as

 [tex]P(\= X  < 35) =  P(\frac{\= X  -  \mu  }{\sigma_{\= x }} <  \frac{35 -35.6}{0.2373 }  )[/tex]

[tex]P(\= X  < 35) =  P(Z< -2.53  )[/tex]

From the z-table  we have that

   [tex]P(Z< -2.53  ) =  0.006[/tex]

So

 [tex]P(\= X  < 35) = 0.006 /tex]

Converting to percentage

      [tex]P(\= X  < 35) =   0.006  * 100 [/tex]

      [tex]P(\= X  < 35) =  0.6 \%[/tex]

Here the probability of koalas mean temperature being less than 35 °C is very small hence the koalas are not healthy

A potential confounding variable for this study is  the population of the koalas because in the first question the population was not taken into account and the probability was  [tex]P(X  < 35) =  32.3 \%[/tex] but when the population was taken into account (i.e  n =  30) the probability became

 [tex]P(\= X  < 35) =  0.6 \%[/tex]  

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