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IR: Graph Interpretation [#permalink] Show Tags New post 25 Jun 2019, 09:43
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At the end of last semester, all 33 students (11 from each of 3 sections) of a particular course were asked how many hours per week they spent studying for the course. This data was combined with the number of points earned by each student in the course. This information is presented in the graph. Grades in the course were calculated using a 20-point scale. To compute the grade, the number of points earned in the course was divided by 50 and then rounded up to the next whole number.Use the drop-down menus to complete each statement so that it is consistent with the information provided.
The median reported time spent studying for all students in the course was ___ hours per week.
A)2
B)2.5
C)3
D)3.5
Section ___ had the smallest average (arithmetic mean) reported time spent studying per week.
A)
B)
C)
The right answers here are
C &
C.
The first question is asking us about the median number of hours across the 33 students. Since 33 is an odd number, we're simply looking for the student who studied more than 16 others, and less than 16 others, or the 17th student. Given that your average IR question should take you about 2.5 minutes, you can simply count this.
5 students study one hour, 9 study two hours. This means that so long as there are 3 or more students who study three hours, its the median. We don't need to count them all, and we now know it's 3.
For calculating the mean, there is one important statement that should make your process much simpler; each section has the SAME number of people. This means that the total number of hours will be the same as the mean number of hours.
Section C has no students studying 5 hours or more, so this is a good place to start. The total value is 26. From there, the quickest method to solve the questions would be to add up the highest values for the other classes until the value exceeds 26.
- Matoo
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