Question

Question 9 View Policies Current Attempt in Progress Impact of College Roommates on Grades In this exercise, we investigate answers to the questions: How much of an effect does your roommate have on your grades? In particular.does it matter whether your roommate brings a videogame to college? A study was conducted involving n 210 first-year students who were randomly assigned a roommate. Table 1 gives summary statistics on grade point average (GPA) for the first semester depending on whether the student and/or the roommate brought a videogame to campus. Student brought bught Sample size Mcan GPA St. Dev vidcogame videogame Roommate No No No Yes 3,128 3.039 2.932 2.754 0,590 0.689 0.699 0.639 No 40 Table 1 Videogames and GPA onsidering only students whose roo n a te does not bring a vid game to campus, find a 90% confidence interval for the difference in mean GPA between students μ. μ r where μ represents the mean GPA for students who do not bring a videogame and 11 represents the mean GPA for students who do bring a videogame. to bring a videogame and those who do not bring a de game Round your answers to three decimal places. The 90% confidence interval is to eTextbook and Media Hint

Answer 1

Since we only have to consider roommates who does not bring videogame,we will be concerned with first 2 rows of data

Now,

muN =3.128

muY =3.039

90% confidence interval is

(3.128-3.039) -+ 1.645 * sqrt( 0.59^2/88 + 0.689^2/44)

=0.089 -+ 1.645*sqrt(0.0039 + 0.0108)

= 0.089 -+ 0.199

(-0.11,0.288)