1. A random sample of bags of potato chips produced by a company has a mean weight of 15.3 ozs., which is greater than the 14.9 oz. mean weight of all bags of chips produced by the company. In this example, 15.3 is called a

2. A sample of 75 people at a local fast-food restaurant found 30 in favor of new fat-free menu items. In this example, what is the sample proportion?

3. Twenty five percent of the students at Midtown University favor a fee increase to pay for the maintenance of the campus gardens. Ninety students will be chosen at random and surveyed about the fee increase. The percent who approve is the statistic of interest. What is the standard deviation of the sampling distribution of this statistic?

4. The annual income of residents in a certain county has a mean of $42,000 and a standard deviation of $10,000. For a survey, 150 residents will be polled and the mean income determined. What is the standard deviation of the sampling distribution for the mean income?

5. In the manufacturing process for ball bearings, the mean diameter is supposed to be 5 mm with a standard deviation of 0.002 mm. One hour, a sample of 10 bearings is drawn and the mean diameter is found to be 4.998 mm. Find a 95% confidence interval for the true mean diameter of bearings produced that hour.
A.4.994 to 5.002 mm
B.4.9967 to 4.9993 mm
C.4.97 to 5.026 mm
D.4.9974 to 4.9986 mm

6. A tool and die company makes dies which are to have a 2-in. diameter. The standard deviation of the produced parts is 0.003-in. Samples of 10 dies are chosen each day and the mean diameter of the sample found. What would be the 95% control limits for a process control chart used by the company?
A.1.9981 to 2.0019 in.
B.1.9991 to 2.0009 in.
C.1.994 to 2.006 in.
D.1.9654 to 2.0346 in.

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