Question 5.66

36. Forty 6-year-olds were randomly selected from the participants in a study investigating childhood obesity. The children’s weights (in kilograms) are arranged below in order from smallest to largest:

16.9 17.0 17.1 17.5 17.7 18.1 18.3 18.6 18.8 18.9
19.1 19.1 19.2 19.5 19.6 19.9 20.0 20.2 20.3 20.4
20.5 20.8 20.8 20.8 21.0 21.3 21.9 22.2 22.5 22.7
22.9 23.0 23.4 23.5 24.4 25.6 26.5 34.2 38.2 44.8

  1. Give the five-number summary of the weights of these 6-year-olds, and then draw a boxplot to represent this summary.
  2. The width of your box, , gives the interquartile range (IQR). Calculate the IQR for these data.
  3. Consider any weights that fall more than above the third quartile or below the first quartile as outliers. Identify any outliers.
  4. Use the information from parts (a) through (c) to draw a modified boxplot of the weight data (similar to the ones shown in Figure 5.17 on page 203).
  5. Which boxplot do you think better represents these data, the one from part (a) or the modified boxplot in part (d)? Why?