Final answer:
The statement regarding Murrysville Regional Hospital's treatment of 20 patients for fireworks-related injuries is an example of descriptive statistics, which summarize actual data collected without making generalizations. Similarly, the determination of the average decrease in tumor size by a scientist is also descriptive statistics.
Step-by-step explanation:
The statement "Last year, during the week of July, Murrysville Regional Hospital reported that they treated 20 patients for fireworks-related injuries." refers to descriptive statistics, because it is summarizing actual data collected without inferring or generalizing beyond the reported week. Descriptive statistics organize and summarize data through numerical summaries or graphs without drawing conclusions about a larger population.
In the context of the example provided, 'The scientist determines the average decrease in tumor size for the drug-treated group,' this also represents descriptive statistics. The average decrease is a summarization of the collected data. It is considered descriptive statistics because it is a numerical summary without making inferences about a general population or larger group.
Both the hospital report and the average decrease in tumor size given by the scientist are ways to organize and summarize data, which are components of descriptive statistics. As opposed to this, inferential statistics would involve using the data to estimate a population parameter, test hypotheses, or make predictions about a larger group based on the sampled data.