Consider an experiment in which adult laboratory mice were fed one of three diets: high fat, low fat, and a control diet. The mice were weighed, received these diets for 2 weeks, and then were weighed again. The table below shows the results of the experiment.

$\begin{array}{|l|l|l|}
\hline \text { Diet } & \text { Gained weight } & \text { Lost weight } \
\hline \text { High Fat } & 79 & 21 \
\hline \text { Low Fat } & 30 & 69 \
\hline \text { Control } & 70 & 30 \
\hline
\end{array}$
-Assuming a null hypothesis of no relationship between diet and weight gain, which of the following values is closest to the expected count of individuals in the control group that gained weight?

Question

Consider an experiment in which adult laboratory mice were fed one of three diets: high fat, low fat, and a control diet. The mice were weighed, received these diets for 2 weeks, and then were weighed again. The table below shows the results of the experiment.
​
​ $\begin{array}{|l|l|l|}
\hline \text { Diet } & \text { Gained weight } & \text { Lost weight } \
\hline \text { High Fat } & 79 & 21 \
\hline \text { Low Fat } & 30 & 69 \
\hline \text { Control } & 70 & 30 \
\hline
\end{array}$
-Assuming a null hypothesis of no relationship between diet and weight gain, which of the following values is closest to the expected count of individuals in the control group that gained weight?

Quizplus · Accepted Answer

To calculate the expected count for the control group that gained weight under the null hypothesis, we first need to find the total number of mice that gained weight and the total number of mice in the control group. The total number of mice that gained weight is $79 + 30 + 70 = 179$. The total number of mice is $79 + 21 + 30 + 69 + 70 + 30 = 299$. The proportion of mice that gained weight is $179/299$. The total number of mice in the control group is $70 + 30 = 100$. Therefore, the expected count of control group mice that gained weight under the null hypothesis is $100 \times (179/299) \approx 60$.

Consider an Experiment in Which Adult Laboratory Mice Were Fed