Page 124 - Statistics for Dummies

108
Part II: Number-Crunching Basics
20
Percentage of people in each group
15
10
5
0
2.5
1.5 Time Spent Filling Out a Survey (n = 50) 5.5
3.5
4.5
Time (minutes)
a
Student Exam Scores (n = 17)
4
Number of students in each group 3 2

Figure 7-2:
Comparing
the shape 1
of a) a
symmetric
histogram
0
and b) a
40 48 56 64 72 80 88
skewed left
histogram. Score
b

As you know from Figure 7-1, the actresses’ ages in Figure 7-1 are skewed
right. Most of the actresses were between 20 and 50 years of age when they
won, with about 27% of them between the ages of 30–35. A few actresses were
older when they won their Oscars; about 6 percent were between 60–65 years
of age, and less than 4% (total) were 70 years old or over (if you add the

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