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MATH 533 Week 4 Quiz (2 Sets) (New) Click Here to Buy the Tutorial For more course tutorials visit

1. A random samples of 1020 satellite radio subscribers were asked, “Do you have a satellite radio receiver in your car?� The survey found that 102 subscribers did, in fact, have a satellite receiver in their car.

2. Each child in a sample of 64 low-income children was administered a language and communication exam. The sentence complexity scores had a mean of 7.62 and a standard deviation of 8.91. Complete parts a through d.

3. In a sample of 60 stores of a certain company, 50 violated a scanner accuracy standard. It has been demonstrated that the conditions for a valid large-sample confidence interval for the true proportion of the stores that violate the standard were not met. Determine the number of stores that must be sampled in order to estimate the true proportion to within 0.05 with 95% confidence using the large-sample method.

4. A company wants to test a randomly selected sample of n water specimens and estimate the mean daily rate of pollution produced by a mining operation. If the company wants a 90% confidence interval estimate with a sampling error of 1.8 milligrams per liter (mg/L), how many water specimens are required in the sample? Assume prior knowledge indicates that pollution readings in water samples taken during a day are approximately normally distributed with a standard deviation equal to 8 mg/L.

5. The white wood material used for the roof of an ancient temple is imported from a certain country. The wooden roof must withstand as much as 100 centimeters of snow in the winter. Architects at a university conducted a study to estimate the mean bending strength of the white roof. A sample of 25 pieces of the imported wood were tested and yielded the statistics x = 74.5 and s = 10.3 on breaking strength (MPa). Estimate the true mean breaking strength of the white wood with a 99% confidence interval. Interpret the result.

Math 533 week 4 quiz