The National Sleep Foundation employed a survey to find out whether hours of sleeping per night are independent of the age (Newsweek, January 19, 2004). The following show the hours of sleep on weeknights for sample of individuals age 49 and younger and for sample of individuals age 50 and older.
Hours of Sleep
Age Fewer than 6 6 to 6.9 7 to 7.9 8 or more Total
49 or younger 30 56 77 77 240
50 or older 36 64 78 82 260
Conduct test of independence to find out whether the hours of sleep on weeknights are independent of age. Use a= .05.
Calculate the value of the? 2 test statistic (to 2 decimals). The p-value is?
Using the total sample of 500, estimate the percentage of people who sleep less than 6, 6 to 6.9, 7 to 7.9, and 8 or more hours on weeknights (to 1 decimal).
Less than 6 hours %
6 to 6.9 hours %
7 to 7.9 hours %
8 or more hours %