Multiple Choice Identify the
choice that best completes the statement or answers the question.


1.

A speed reading course claims that it can boost reading speeds to 1050 words per
minute. In a random sample of 49 people who took the course, the average was 1020 words per
minute, with a standard deviation of 90 words per minute. What is the zvalue rounded to the
nearest hundredth?
a.  The zvalue is –2.33.  b.  The zvalue is
–16.33.  c.  The zvalue is –1.96.  d.  The zvalue is
1.96. 


2.

An automobile insurance company claims that its rates for teenage drivers
average $410 less per year than the same coverage from another company. In a random sample of 35
customers, the average savings was $390 per year, with a standard deviation of $55 per year. What is
the zvalue rounded to the nearest hundredth?
a.  The zvalue is 1.87  b.  The zvalue is 1.87  c.  The zvalue
is –2.15.  d.  The zvalue is 2.15 


3.

Suppose that a certain website claims that it averages 4.7 hours of downtime per
month. (Downtime is time that the site is not available.) In a random sample of 17 months, the
average downtime was 4.9 hours per month, with a standard deviation of 0.5 hours per month. What is
the zvalue rounded to the nearest hundredth?
a.  The zvalue is 1.65.  b.  The zvalue is 2.21  c.  The zvalue
is 1.65.  d.  The zvalue is 2.21 
