The mathematical purpose of this lesson is for students to use data from a random sample and simulation to estimate a population proportion and to understand margin of error for a population proportion estimate. Students continue to explore the idea of simulating a sampling distribution to understand the expected variability and apply that to compute a margin of error for their estimate. They also learn that larger samples tend to result in lesser margins of error. When students interpret the meaning of the margin of error in the context of a problem, they are reasoning abstractly and quantitatively (MP2). When students use and analyze data to make connections between sample size and margin of error, they are looking for and making use of structure (MP7).