Textbook Authors Must Be Careful That the Reading Level of Their

Essay

Textbook authors must be careful that the reading level of their book is appropriate for the target audience. Some methods of
assessing reading level require estimating the average word length. We've randomly chosen 20 words from a randomly
selected page in Stats: Data and Models and counted the number of letters in each word:
5, 5, 2, 11, 1, 5, 3, 8, 5, 4, 7, 2, 9, 4, 8, 10, 4, 5, 6, 6
-For a more definitive evaluation of reading level the editor wants to estimate the text's
mean word length to within 0.5 letters with 98% confidence. How many randomly selected
words does she need to use?