Dr. Mack Lemore, an expert in consumer behavior, wants to estimate the average amount of money that people spend in thrift shops. He takes a small sample of 8 individuals and asks them to report how much money they had in their pockets the last time they went shopping at a thrift store. Here is the data: 17.24, 20.63, 26.76, 19.85, 18.24, 23.38, 29.55, 28.29. He wishes to test the null hypothesis that the average amount of money people have in their pockets is equal to $20. Calculate the test statistic to two decimal places. Take all calculations toward the answer to three decimal places.
| Values ( X ) | Σ ( Xi- X̅ )2 | |
| 17.24 | 33.0913 | |
| 20.63 | 5.5814 | |
| 26.76 | 14.1941 | |
| 19.85 | 9.8753 | |
| 18.24 | 22.5863 | |
| 23.38 | 0.1502 | |
| 29.55 | 43.0008 | |
| 28.29 | 28.0635 | |
| Total | 183.94 | 156.5429 |
Mean X̅ = Σ Xi / n
X̅ = 183.94 / 8 = 22.992
Sample Standard deviation SX = √ ( (Xi - X̅
)2 / n - 1 )
SX = √ ( 156.5429 / 8 -1 ) = 4.729
Test Statistic :-
t = ( X̅ - µ ) / ( S / √(n))
t = ( 22.992 - 20 ) / ( 4.729 / √(8) )
t = 1.79
Dr. Mack Lemore, an expert in consumer behavior, wants to estimate the average amount of money...
Dr. Mack Lemore, an expert in consumer behavior, wants to estimate the average amount of money that people spend in thrift shops. He takes a small sample of 8 individuals and asks them to report how much money they had in their pockets the last time they went shopping at a thrift store. Here are the data: 19, 43, 12, 18, 19, 33, 20, 14. Find the upper bound of a 95% confidence interval for the true mean amount of...
Dr. Mack Lemore, an expert in consumer behavior, wants to estimate the average amount of money that people spend in thrift shops. He takes a small sample of 8 individuals and asks them to report how much money they had in their pockets the last time they went shopping at a thrift store. Here are the data: 14.73, 28.89, 27.73, 16.35, 21.56, 22.34, 28.73, 26.88. Find the lower bound of a 98% confidence interval for the true mean amount of...