Question

he 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

A. The letter t occurs less than 26 times on approximately 170 of these pages.

B. The letter t occurs less than 26 times on approximately 15 of these pages.

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

D. The letter t occurs more than 26 times on approximately 80 of these pages.

Answer 2

review the empirical rule: https://i.ytimg.com/vi/uUb-lBQwd9U/maxresdefault.jpg

26 is 1 standard deviation below the mean (44-18 = 26)

look at the curve to see what % of values falls below 1 standard deviation

from there, multiply your percentage by 500 pages