3)b. For boxplot, make the ruler first, then mark the points
and draw the box and whiskers. A rubber ruler (axis) will not
convey what the boxplot is supposed to--the relative lengths of the 4
parts.
d. Nobody has 1 ear pierced, about 7 have 3
piercings; 45 have 2, the most common. Women prefer symmetry, at
least thru 4 piercings. (Men do have 1 ear pierced)
6) a. A stemplot is supposed to be quick. The quick way
is to read the numbers as they come and put the leaves on in that
order,
as if you're tallying. Trying to order on the first pass is slow
and inaccurate; defeats the purpose.
c. The French presidency is a more ceremonial honored post,
providing stability; the day-to-day policy making is done by the prime
minister, who can be voted out in a moment. So it isn't
surprising that the French presidents are somewhat older on average.
7) This problem caused people the most trouble. We'll leave
these for now but they'll be back; so figure them out.
c) 8 is the 23rd percentile if there is 23% of the
area/population below 8.
8) I hoped that drawing and labeling a normal distribution would lead you to see that this gives negative hours of tv watching, an impossibility, unfortunately. The actual distribution is strongly skewed right, with a lot of students at 0 and in low hours per week, an outlier at 100 hrs (this is a student?)
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