Question

lW Wola It affect the minimum number you need to survey? Why? O CO lilOellt ana a new survey were commissioned, Use the following information to answer the next five exercises: Suppose the marketing company did do a survey. They randomly surveyed decisions. We are interested in the population proportion of households where women make the majority of the purchasing decisions. 200 ho ds and found that in 120 of them, the woman made the majority of the purchasing 64. Identify the following: 65. Define the random variables X and P' in words. 66. Which distribution should you use for this problem? 67 Construct a 95% confidence interval for the population proportion of households where the women ake the of the purchasing decisions. State the confidence interval, sketch the graph, and calculate the error bound. rity 68. List two difficulties the company might have in obtaining random results, if this survey were done by email. Use the following information to answer the next five exercises: Of 1,050 randomly selected adults, 360 identified themselves as manual laborers, 280 identified themselves as non-manual wage earmers, 250 identified themselves as mid- level managers, and 160 identified themselves as executives. In the survey, 82% of manual laborers preferred trucks, 62% of non-manual wage earners preferred trucks, 54% of mid-level managers prefemed trucks, and 26% of executives refe ed trucks. 69. we are interested in finding the 95% confidence interval for the percent of executives who prefer trucks. Define random variables X and P' in words.

Answer 1

64:

(a) x = 120

(b) n = 200

(c)  

65:

Here X shows the number of woman made the majority of the purchasing decision in sample.

P' shows the proportion of woman made the majority of the purchasing decision in sample.

66:

Standard normal distribution

67:

Following is the graph:

0.496 053 056 0.6 0.635 0.669 0.704

68:

In that case, sample will not be simple random sample and responses are voluntary. So it may not represent the population correctly.