The survival times of guinea pigs inoculated with an infecti…

The survival times of guinea pigs inoculated with an infectious viral strain vary from animal to animal. The distribution of survival times is strongly skewed to the right. The [blank] says that the average survival time of a large number of infected guinea pigs has a distribution that is close to the normal distribution.

In the 2010 U.S. Census, one of the questions asked was “How…

In the 2010 U.S. Census, one of the questions asked was “How many people live in your household?”. The table below shows the probability distribution of this variable, X, which have values 1, 2, 3, 4, 5, 6, or 7.  X (Number of People) 1 2 3 4 5 6 7 P(X = x) ??? 0.336 0.158 0.137 0.063 0.024 0.015 What is the expected value for X?