standard_description: Develop a probability distribution for a random variable defined for a sample space in which probabilities are assigned empirically; find the expected value. For example, find a current data distribution on the number of TV sets per household in the United States, and calculate the expected number of sets per household. How many TV sets would you expect to find in 100 randomly selected households?
problem_activity: Are the following two expressions equivalent? Explain your reasoning using the properties of operations. Provide examples to support your reasoning.
Expression 1:
$${(x-y)-z }$$
Expression 2:
$${x-(y-z)}$$


aligns: no