Stat 1350 - Elementary Statistics
Graded Homework Assignment 6
KEY
1.
College tuition.
A stemplot of the tuition charged by 116 colleges in Illinois is given below. The stems
are thousands of dollars and the leaves are hundreds of dollars. For example, the highest tuition is
$38,600 and appears as leaf 6 on stem 38.
(a) Find the five-number summary of Illinois college tuitions. You see that the stemplot already arranges the

(b) Would the mean tuition be clearly smaller than the median, about the same as the median, or clearly larger

2.
Where are the young more likely to live?
A stemplot of the percentage of residents aged 18 to 34 in
each of the 50 states is given below. The stems are whole percents and the leaves are tenths of a
percent.
(a) The shape of the distribution suggests that the mean will be larger than the median. Why?
(b) Find the mean and median of these data and verify that the mean is larger than the median.
3.
How many calories does a hot dog have?
Consumer Reports
magazine presented the following data
on the number of calories in a hot dog for each of 17 brands of meat hot dogs:
Make a stemplot and find the five-number summary.
The stemplot shows important facts about the distribution that the numerical summary does not tell us.

4.
Returns on common stocks.
Example 5
informs us that financial theory uses the mean and
standard
deviation
to describe the returns on investments. A histogram of the returns of all New York Stock
Exchange common stocks in one year is given below. Are the mean and standard deviation suitable as a

5.
Minority students in engineering.
Figure
11.11
is a histogram of the number of minority students
(black, Hispanic, Native American) who earned doctorate degrees in engineering from each of 152
universities in the years 2000 through 2002. The classes for histogram below are 1-5, 6-10, 11-15, 16-
20 and so on.
(a) What is the position of each number in the five-number summary in a list of 152 observations arranged from
smallest to largest?
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