Question

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QUESTION 7

1. Suppose the observational units in a study are the patients arriving at an emergency room on a given day, 11 Nov 2019. For the following indicate whether it can legitimately be considered a variable or not:

   Whether or not men have to wait longer than women

   yes

   no

5 points   

QUESTION 8

1. A survey company published results of a survey stating that 56% of the 600 randomly sampled residents planned to set off firereworks on July 4th.

   Determine the margin of error for the 56% point estimate using a 95% confidence level.

   Give your answer as a decimal rounded to two decimal places. (like .02 or .07 or .12)

6 points   

QUESTION 9

1. SAT scores (out of 2400) are distributed normally with a mean of 1480 and a standard deviation of 320. Suppose a school council awards a certificate of excellence to all students who score at least 1900 on the SAT, and suppose we pick a student at random. What is the chance they will have a score at least 1900?

   (Give your answer in decimal form to 4 places, like .0304 or .1421)

6 points   

QUESTION 10

1. Suppose the observational units in a study are the patients arriving at an emergency room on a given day, Nov 11, 2019.

   Number of patients that arrive before noon

   is a qualitative variable

   is a quantitative variable

   is not a variable

4 points   

QUESTION 11

1. Suppose the observational units in a study are the patients arriving at an emergency room on a given day, Nov 11, 2019. For the following indicate whether it can legitimately be considered a variable or not:

   Blood Type

2. a.

   yes

   b.

   no

1. Suppose you are interested in the population of all college students in the US and that you collect data from all students from FIT.

   Is the following a parameter or statistic?

   The proportion of your school's students who are Business Majors

   a.

   parameter

   b.

   statistic

1. A company claims that 80% of its customers are under 30. You suspect it is less than this. You take a random sample of 200 customers to test this and find out that 75% of your sample are under 30. What is the alternative hypothesis here?

   a.

   The proportion of customers under 30 is less than 75%

   b.

   The proportion of customers under 30 is less than 80%

   c.

   The proportion of customers under 30 is equal to 75%

2. A 99% confidence interval is smaller in size than a 95% confidence interval because it is more accurate.

   True    False

Answer 1