The figure displays several possible finite probability models for rolling a die. We can learn which model is actually accurate for a particular die only by rolling the die many times. However, some of the models are not valid. That is, they do not obey the rules.
\begin{tabular}{|l|l|l|l|l|l|}
\hline \multicolumn{6}{|c|}{Probability} \\
\hline Outcome & Madel 1 & Musel2 & Mudel) & Model 4 & \\
\hline & \( 1 / 7 \) & 13 & 1/3 & 1 & 2 \\
\hline & 17 & 1/6 & 1/6 & 1 & \\
\hline & 1,P & 1/4 & 1/6 & 2 & \\
\hline & 18 & 0 & 1/6 & 1 & \\
\hline & 1/7 & 1/6 & 1/6 & 1 & \\
\hline & 1/7 & 1/6 & 1/6 & 2 & \\
\hline
\end{tabular}
Which are valid and which are not? Select the best answer, with the correct explanation of what is wrong in the case of the invalid models.
Model 2 is valid. Model 4 is not valid, because it has some probabilities that are greater than 1 . It is impossible to decide whether Models 1 and 3 are valid, since we do not know whether the events are disjoint.
None of the given models is valid. Models 1, 3, and 4 have probabilities that do not sum to 1. Model 4 has some probabilities that are greater than 1 . Model 2 has some probabilities that do not match how a die works; for example, it is nonsensical that the probability of rolling a 4 is 0 .
Only Model 2 is valid. Models 1,3 , and 4 have probabilities that do not sum to 1 . Model 4 has some probabilities that are greater than 1 .
Models 1, 2, and 3 are valid. Model 4 is not valid, because it has some probabilities that are greater than 1 .