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3.2.1: Exercises

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    1. Imagine a survey of students, faculty, and administrators is conducted to gauge the importance of using social media to interact with peers and colleagues. The data is summarized in the two-way table below.
       

      Very important

      Somewhat important

      Not important

      Total

      Students

      65

      82

      52

      199

      Faculty

      15

      31

      36

      82

      Administrators

      9

      15

      15

      39

      Total

      89

      128

      103

      320
      1. Name one way in which students, faculty, and administrators differ in their attitudes regarding social media.





         
      2. What is the probability that a subject felt social media was very important? Use probability notation in your answer. Write your answer as a fraction and decimal rounded to three decimal places.






         
      3. What is the probability that a subject felt social media was somewhat important? Use probability notation in your answer. Write your answer as a fraction and decimal rounded to three decimal places.





         
      4. What is the probability that a subject felt social media was not important? Use probability notation in your answer. Write your answer as a fraction and decimal rounded to three decimal places.






         
      5. What is the probability that a subject is a student? Use probability notation in your answer. Write your answer as a fraction and decimal rounded to three decimal places.






         
      6. What is the probability that a subject is a faculty? Use probability notation in your answer. Write your answer as a fraction and decimal rounded to three decimal places.




         
      7. What is the probability that a subject is an administrator? Use probability notation in your answer. Write your answer as a fraction and decimal rounded to three decimal places.




         
      8. What is the probability that a subject is a student and felt that social media was very important? Use probability notation in your answer. Write your answer as a fraction and decimal rounded to three decimal places.





         
      9. What is the probability that a subject is a faculty and felt that social media was very important? Use probability notation in your answer. Write your answer as a fraction and decimal rounded to three decimal places.





         
      10. What proportion of students felt that social media was very important? Use probability notation in your answer. Write your answer as a fraction and decimal rounded to three decimal places.





         
      11. What proportion of those that felt that social media was somewhat important were faculty? Use probability notation in your answer. Write your answer as a fraction and decimal rounded to three decimal places.





         
      12. Which is more likely: Finding a student who thinks social media is not important, or finding a faculty member who thinks social media is not important. Defend your response.






         
    2. The forecast for an upcoming weekend shows a 30% chance of rain on Saturday and a 20% chance of rain on Sunday. Assume these events are independent. What is the probability of it raining on both days?






       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

       

    This page titled 3.2.1: Exercises is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Hannah Seidler-Wright.