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]