A survey was done at Ketcham High School to determine the ef

A survey was done at Ketcham High School to determine the effect of time spent on studying and grade point average. The table below shows the results for 10 students randomly selected a) Enter the data in your calculator and use it to generate the equation for the line of best fit. Round your slope to the nearest tenth and round your y-intercept to the nearest integer b) According to the linear regression model from part (a), what GPA, to the nearest integer, would result from studying for 15 hours in a given week? Justify your answer. c) A passing average is defined as a 65% or above. Does the model predict a passing average if the student spends no time studying in a given week? Justify your answer. d) For each additional hour that a student studies per week, how many points does the model predict a GPA will rise? Explain how you arrived at your answer. e) Create a scatterplot of the data.

Solution

a) The quation of best fit is:

Equation: Y = 1.68*X + 62

b) Now Put x = 15

Y = 1.68*15 + 62

Y = GPA = 87.2 or 87

c) Put x = 0

Y = 62

So, the model doesnot predict because Y < 65% when no time is spent on study.

d) The coefficient of X in equation Y = 1.68*X + 62 will tell y=us this.

So, for every 1 hour increase (X value), GPA would increase by 1.68