Question 1. A large manufacturing company in Indianapolis produces valves for the chemical industry. According to specifications, one particular valve is supposed to have a five-inch opening on the side. Quality control inspectors take random samples of these valves just after the hole is bored. They measure the size of the hole in an effort to determine if the machine is out-of-adjustment. The measurement of the diameter of the hole represents which level of data?
a) nominal
b) ratio
c) ordinal
d) interval
Question 2. Suppose 30% of a population possess a given characteristic. If a random sample of size 1200 is drawn from the population, then the probability that less than 348 possess that characteristic is _______.
a) 0.2900
b) 0.2764
c) 0.2236
d) 0.7764
Question 3 .Mary Flindt, a Marketing Director with Epsilon Airlines, is assessing the relative importance of the "total flight" experience. An item on a survey questionnaire distributed to 100 of Epsilon's customers asked them to rate the importance of "cabin space" on a scale of 1 to 10 (with 1 meaning "not important" and 10 meaning "highly important"). Her staff assembled the following statistics from the responses.
Cabin Space
Mean 7.2
Standard Deviation 3.7
If Mary concludes that the average rate of "cabin space" for all customers is 7.2, she is using ________.
a) an interval estimate
b) a statistical parameter
c) a point estimate
d) a range estimate