The peak shopping time at home improvement store is between 8:00am-11:00 am on Saturday mornings. Management at the home improvement store randomly selected 115 customers last Saturday morning and decided to observe their shopping habits.
They recorded the number of items that each of the customers purchased as well as the total time the customers spent in the store. Identify the types of variables recorded by the home improvement store. A) number of items - discrete; total time - continuous
B) number of items - continuous; total time - continuous
C) number of items - continuous; total time - discrete
D) number of items - discrete; total time - discrete
Q. 2Construct a 90 confidence interval for the population mean, . Assume the population has a normal distribution.
In a recent study of 22 eighth graders, the mean number of hours per week that they played video
games was 19.6 with a standard deviation of 5.8 hours. Round to the nearest hundredth.
A) (17.47, 21.73 ) B) (18.63, 20.89 ) C) (5.87, 7.98 ) D) (19.62, 23.12 )
Q. 3At a tennis tournament a statistician keeps track of every serve. The statistician reported that the mean serve speed of a particular player was 101 miles per hour (mph) and the standard deviation of the serve speeds was 14 mph.
If nothing is known about the shape of the distribution, give an interval that will contain the speeds of at least three-fourths of the player's serves. A) 73 mph to 129 mph B) 87 mph to 115 mph
C) 59 mph to 143 mph D) 129 mph to 157 mph
Q. 4The government of a town needs to determine if the city's residents will support the construction of a new town hall. The government decides to conduct a survey of a sample of the city's residents.
Which one of the following procedures would be most appropriate for obtaining a sample of the town's residents? A) Survey a random sample of persons within each geographic region of the city.
B) Survey a random sample of employees at the old city hall.
C) Survey every 8th person who walks into city hall on a given day.
D) Survey the first 300 people listed in the town's telephone directory.
Q. 5the number of pills in an aspirin bottle
A) discrete B) continuous
Q. 6Construct a 98 confidence interval for the population mean, . Assume the population has a normal distribution. A study of 14 car owners showed that their average repair bill was 192 with a standard deviation of 8. Round to the nearest cent.
A) (186.33, 197.67 ) B) (222.33, 256.10 ) C) (328.33, 386.99 ) D) (115.40, 158.80 )
Q. 7The length of time it takes college students to find a parking spot in the library parking lot follows a normal distribution with a mean of 3.0 minutes and a standard deviation of 1 minute.
Find the probability that a
randomly selected college student will take between 1.5 and 4.0 minutes to find a parking spot in the library
lot.
A) 0.7745 B) 0.4938 C) 0.0919 D) 0.2255
Q. 8The average score of local students on a college entrance exam is 110, with a standard deviation of 5. The distribution is roughly bell shaped. Use the Empirical Rule to find the percentage of local students with scores above 120.
A) 2.5 B) 5 C) 95 D) 97.5
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