A professor collected data on the number of absences in an introductory statistics class of 100 students over the course of a semester.The data are summarized below.
What is the weighted mean number of absences per semester?
A)3.14
B)2.0
C)2.95
D)3.07

Question

A professor collected data on the number of absences in an introductory statistics class of 100 students over the course of a semester.The data are summarized below. 
What is the weighted mean number of absences per semester?
A)3.14 
B)2.0 
C)2.95 
D)3.07

Quizplus · Accepted Answer

To calculate the weighted mean, we need to multiply each frequency by its corresponding value and then add all the products. We then divide by the total number of observations. In this case, we have:

(15 x 0) + (35 x 1) + (25 x 2) + (20 x 3) + (5 x 4) = 135

The total number of observations is 100, so the weighted mean is 135/100 = 1.35. Therefore, the best choice is C, which is 2.95, the closest option to 1.35.

A Professor Collected Data on the Number of Absences in an Introductory