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In a regression analysis of customer satisfaction versus wait time, the standard error of the residuals is 0.5 on a 5-point scale. What does this tell us about the model’s predictions?

A restaurant’s daily lunch revenue follows a normal distribution with mean $800 and standard deviation $100. Using the empirical rule, approximately what percentage of days will have revenue between $600 and $1000?

A financial advisor is analyzing the annual returns of different mutual funds.   Monthly Returns for 2024 (in percentages) Fund A: -2 15 12 -5 18 4 9 22 -8 16 7 12 Fund B: 6 9 7 10 5 8 11 7 9 6 8 10 Calculate the standard deviation for both funds and determine which statement is correct about their variability.

The table below shows the number of state-registered automatic weapons and the murder rate for several Northwestern states.   x 11.9 8.4 6.7 3.9 2.6 2.7 2.3 0.3 y 13.9 11 9.6 7 6.3 6.2 6.2 4   x = thousands of automatic weapons y = murders per 100,000 residents   Use the data from the table to calculate the line of best fit.

You have collected data on the number of text messages sent daily by 25 students: 45, 23, 67, 89, 34, 56, 78, 45, 34, 23, 67, 89, 90, 45, 34, 67, 78, 56, 45, 34, 23, 67, 89, 78, 56   Which type of graph would be most appropriate to show the distribution of daily text messages?

What is the correct order of the statistical investigative process?

When examining a scatterplot with a line of best fit, a data point falls above the line. What does this tell you about the residual for this point?

A neighborhood grocery store collects data about shopping patterns. They find that 60% of customers buy fresh produce and 25% buy organic products. If these events are independent, which of the following must be true?

A survey asked 200 college students about their preferred study location (library, home, or café) and their year in school (first-year or senior). Which type of graph would best show how study location preferences differ between first-year and senior students?

Giving a test to a group of students, the grades and gender are summarized below:   Student Grades Gender A B C Total Male 17 10 18 45 Female 7 19 11 37 Total 24 29 29 82   If one student is chosen at random, find the probability that the student got a ‘C’ GIVEN they are female.