Question

The distribution of the number of occurrences of the letter t on the pages of a book is found to be a normal distribution with a mean of 44 and a standard deviation of 18. If there are 500 pages in the book, which sentence most closely summarizes the data?

Answer 1

The letter t occurs more than 26 times on approximately 420 of these pages.

Explanation:

1 standard deviation below mean = M - SD

= 44 - 18 = 26

This implies that that "26" is 1 s.d. below the mean, which is at the 16th percentile.

Thus, there is a 0.16 chance that "t" will occur less than 26 times on any single page.

consequently, there is a 0.84 chance that it will occur more than 26 times on any single page.