When a consulting firm conducted a survey of 1100 employee a

When a consulting firm conducted a survey of 1100 employee at medium sized and large companies to determine how dissatisfied employees were with their jobs they found that the 473 reported that they experienced strong dissatisfaction with their jobs. Please provides a 90% confidence interval estimate of the proportion of employee who reported being dissatisfied [0.3809, 0.4791] [0.3993, 0.4607] [0.4054, 0.4546] [0.4116, 0.4484] [0.4218, 0.4382] 120 randomly selected students at a certain large university report that they carry an average of $80. Assume the population standard deviation is $15. Please provide a 95% confidence interval estimate of the population mean amount carried by all students at this university. [79.66.80.34] [78.66, 81.34] [77.32, 82.68] [76.14, 83.86] [75.71, 84.29] Wall Street securities firms recently paid out record year-end average bonuses of $125,500 per employee. Suppose we drew a sample of n=40 employees at the Jones & Ryan securities firm to test whether their mean year-end bonus is different from $125,500 for the population, and found that the sample mean is $118,000. Assume sigma = $30,000. The two hypotheses to be tested are: H0: mu = 125,500 and Ha; mu 125,500. What is the p-value? 0.0500 0.0571 0.0857 0.0985 0.1142

Solution

1.

Note that              
              
p^ = point estimate of the population proportion = x / n =    0.43          
              
Also, we get the standard error of p, sp:              
              
sp = sqrt[p^ (1 - p^) / n] =    0.014927096          
              
Now, for the critical z,              
alpha/2 =   0.05          
Thus, z(alpha/2) =    1.644853627          
Thus,              
Margin of error = z(alpha/2)*sp =    0.024552887          
lower bound = p^ - z(alpha/2) * sp =   0.405447113          
upper bound = p^ + z(alpha/2) * sp =    0.454552887          
              
Thus, the confidence interval is              
              
(   0.4054   ,   0.4546   ) [ANSWER, C]

*******************************************

Hi! Please submit the next part as a separate question. That way we can continue helping you! Please indicate which parts are not yet solved when you submit. Thanks!