Low birth weight rates. A birth weight of less than 2500 grams

(about 5.5 pounds) qualifies as “low birth weight” according to international standards. Table 3.10 lists low birth weight rates (per 100 births) by country for the year 1991 in 109 countries.

(a) Explore these data with a stemplot. Use an axis multiplier of ×10 and quintuple split stem values to draw your plot. After creating the plot, provide a narrative description of its shape, location, and spread.

(b) Observations in this data set can be ranked from 1 to 109. When ranks are tied, the average rank is assigned to each item in the tied set. For example, Finland, Ireland, Norway, and Sweden are tied for ranks 2 through 5. Therefore, these four countries share a rank of . We then resume ranking where we left off:

Belgium is initially ranked as sixth but is tied with nine other nations with a value of 5. Therefore, positions 6–15 are tied in the ordered array sharing a rank of . Where does the United States rank in this listing?