In the Past,of All the Students Enrolled in "Basic Business

Multiple Choice

In the past,of all the students enrolled in "Basic Business Statistics" 10% earned A's 20% earned B's,30% earned C's,20% earned D's and the rest either failed or withdrew from the course.Dr Johnson is a new professor teaching "Basic Business Statistics" for the first time this semester.At the conclusion of the semester,in Dr.Johnson's class of 60 students,there were 10 A's,20 B's,20 C's,5 D's and 5 W's or F's.Assume that Dr.Johnson's class constitutes a random sample.Dr Johnson wants to know if there is sufficient evidence to conclude that the grade distribution of his class is different than the historical grade distribution. Calculate the chi-square statistic.

A) 9.5
B) 3.03
C) 2.33
D) 16.4