Each year the director of the reading program in a school district administers a standard test of reading skills. Then the director compares the average score for his district with the national average. Figure 2.17 was presented to the school board in the year 2008.

a. Obtain a truncated version of Fig. 2.17 by sliding a piece of paper over the bottom of the graph so that the bars start at 16.
b. Repeat part (a), but have the bars start at 18.
c. What misleading impression about the year 2008 scores is given by the truncated graphs obtained in parts (a) and (b)?

Average reading scores 20 18 16 9 14 a 12 4 0 2003 2004 2005 2006 2007 2008 Year District average 11 National average