Loraine Is Enrolled in an Algebra Class That Meets 5 $\frac { 1 } { 2 } \mathrm { hr } / \mathrm { day }$

Essay

Loraine is enrolled in an algebra class that meets 5 days per week. Her instructor gives a test every Friday. Loraine has a study plan and keeps a portfolio with notes, homework, test corrections, and vocabulary. She also records the amount of time per day that she studies and does homework. The following data represent the amount of time she studied per day and her weekly test grades.
a. Graph the points on a rectangular coordinate system. Do the data points appear to follow a linear trend?
b. Find a linear equation that relates Loraine's weekly test score y to the amount of time she studied per day x. (Hint: Pick the leftmost and rightmost ordered pairs from the observed data, and find an equation of the line through the points.)
c. How many minutes should Loraine study per day in order to score at least 95% on her weekly examination? Would the equation used to determine the time Loraine needs to study to get 95% work for other students? Why or why not?
d. If Loraine is only able to spend $\frac { 1 } { 2 } \mathrm { hr } / \mathrm { day }$ y studying her math, predict her test score for that week.