Name:                                                             :
Group (circle one): 1    2    3    4
Intro-Stat, Math 203, Candy bar Quiz 3
  1. The probabilities associated with the number of states that students in this class have visited are given in the table below. Use these probabilities to answer the following questions.
States Visited 0 to 5 6 to 10 11 to 15 16 to 20 21 or more
Probability 0.03   0.30 0.28 0.12
    1. What is the probability that a random student in this class has visited 6 to 10 states?

      2.  

       
       
       
       
       

    2. What is the probability that a random student in this class has visited more than 15 states?

      3.  

       
       
       
       
       
       

    3. What is the probability that a random student in this class has NOT visited from 11 to 15 states?

      4.  

       
       
       
       
       
       

    4. Which is more likely, a student that has visited 11 to 15 states, or a student that has visitied 16 to 20 states?

      5.  

       
       
       
       
       
       

  1. AcheAway Labs, a pharmaceutical company, has developed a new pain-relief medication for arthritis sufferers. Thirty patients in need of pain relief from arthritis are available. Each subject will be treated and asked one hour later, "About what percentage of pain relief did you experience?"
    1. Why should AcheAway not simply administer the new drug and record the patients' responses?

      2.  

       
       
       
       
       
       
       

    2. Draw an outline of an experiment to compare the drug's effectiveness with that of aspirin and a placebo. Use equal sized groups (10 each) for the experiment.

      3.  

       
       
       
       
       
       
       
       
       
       

    3. What does it mean to say that this experiment is double blind? What might go wrong if it were only single blind?

      4.  

       
       
       
       
       
       
       

    4. Pick a seed value (a whole number) and record it here:                . Now, seed your calculator with this value (enter your seed value and then press [STO>] rand [ENTER]), and use the randInt command to assign each patient (say patient 1 to 30) to each of the three groups (new drug, aspirin or placebo). Give an explanation of how you used your randInt command to accomplish this.

      5.