MATH 225N Week 8 Assignment; Linear Regression Equations

1. Question: Annie owns a tutoring service. For each tutoring session, she charges $75 plus $35 per hour of work. A linear equation that expresses the total amount of money Annie earns per tutoring session is y=75+35x. What are the independent and dependent variables? What is the y-intercept and the slope? 2. Question: George is an avid plant lover and is concerned about the lack of daffodils that grow in his backyard. He finds the growth of the daffodils, G, is dependent on the percent of aluminum measured in the soil, x, and can be modeled by the function …. G(x)=16−4x….. Draw the graph of the growth function by plotting its G-intercept and another point. So, (7,−12)is another point on the graph of G(x). 3. Question: What percent of aluminum in the soil must there be for the daffodils to grow only by 5centimeters? …. Round your final answer to the nearest whole number….. 03 percent$3 text{percent}$3 percent 4. Question: The scatter plot below shows data relating competitive chess players' ratings and their IQ. Which of the following patterns does the scatter plot show? 5. Question: The scatter plot below shows data relating total income and the number of children a family has. Which of the following patterns does the scatter plot show? 6. Question: The number of quetions marked incorrect on a statistics midterm, y, is dependent on the pages of notes a student wrote over the semester, x, and can be modeled by the function y(x)=30−3.5x. Draw the graph of the function by plotting its y-intercept and another point. 7. Question: How many pages of notes did a student take if they had 12 problems marked incorrect on the statistics midterm? 8. Question: A shoe designer explored the relationship between the percent of defects and the percent of new machines at various production facilities throughout the state. The designer collects information from 6 of their facilities, shown in the table below. 9. Question: Using the linear relationship graphed above, estimate the percent of new machines if there is12% defects in the shoes at various production facilities. 10. Question: A department store manager explored the relationship between the percent of customers that wait more than 7 minutes in line and the percent of customers that purchase last minute items at checkout. The manager collects information from 5 checkout lines, shown in the table below. Use the graph below to plot the points and develop a linear relationship between the percent of waiting customers and the percent of last minute purchases. 11. Question: Using the linear relationship graphed above, estimate the percent of last minute purchases if 40% of the customers wait more than 7 minutes in line. 12. Question: A government agency explored the relationship between the percent of public colleges and the percent of freshmen that stay home during college. The researcher collects information from 5 states, shown in the table below. Use the graph below to plot the points and develop a linear relationship between the percent of public colleges and the percent of freshmen that stay home during college. 13. Question: Using the linear relationship graphed above, estimate the percent of freshmen that stay in-state if there are 45% public colleges 14. Question: Describe the relationship between the independent variable, x, and the dependent variable, y, if the correlation is positive. 15. Question: Which of the following patterns does the scatter plot show? 16. Question: Horace keeps track of the amount of time he studies and the score he gets on his quiz. The data are shown in the table below. Which of the scatter plots below accurately records the data? 17. Question: An owner of multiple online clothing stores explored the relationship between the percent of on-call service representatives and the percent of purchases over $75 at the same stores. The owner collects information from 6 of their online stores, shown in the table below. Use the graph below to plot the points and develop a linear relationship between the percent of on-call service representatives and the percent of purchases over $75. 18. Question: Using the linear relationship graphed above, estimate the percent of over $75 purchases if there are 40% on-call service representatives.