3) In today's economy, everyone has become savings savvy. It is still believed, though, that a higher percentage of women than men clip coupons. A random survey of 180 female shoppers indicated that 139 clipped coupons while 50 out of 100 men did so. At a = 0.01, is there sufficient evidence that the proportion of couponing women is higher than the proportion of couponing men? Use the P-value method. Show all details and use the cdf function in your calculator.

An economist predicts that in the next 50 years gas will be 0.02 based on the last 7 months of 2015. What type of error did she make ? Extrapolation? Simpson’s paradox? Influential outlier? Volunteer sample?

Levi-Strauss Co manufactures clothing. The quality control department measures weekly values of different suppliers for the percentage difference of waste between the layout on the computer and the actual waste when the clothing is made (called run-up). The data is in the table, and there are some negative values because sometimes the supplier is able to layout the pattern better than the computer. Do the data show that there is a difference between some of the suppliers? Test at the 1% level. Run-ups for Different Plants Making Levi Strauss Clothing Difference Plant Plant 1 11.9 Plant 1 3.9 -10.6 Plant 1 Plant 1 Plant 1 Plant 1 Plant 1 Plant 1 Plant 1 Plant 1 Plant 1 Plant 1 Plant 1 Plant 1 Plant 1 Plant 1 Plant 1 Plant 1 Plant 1 Plant 1 Plant 1 Plant 1 Plant 2 Plant 2 Plant 2 Plant 2 Plant 2 Plant 2 Plant 2 Plant 2 Plant 2 Plant 2 Plant 2 Plant 2 Plant 2 Plant 2 Plant 2 Plant 2 Plant 2 Plant 2 Plant 2 Plant 2 Plant 2 Plant 2 Plant 3 Plant 3 Plant 3 Plant 3 Plant 3 Plant 3 Plant 3…

The control department of a light bulb manufacturer randomly picks 4400 light bulbs from the production lot every week. The records show that, when there is no malfunction, the defect rate in the manufacturing process (due to imperfections in the material used) is 1% . When 1.5% or more of the light bulbs in the sample of 4400 are defective, the control unit calls repair technicians for service.   Answer the following. (If necessary, consult a list of formulas.) (a)Find the mean of p , where p is the proportion of defective light bulbs in a sample of 4400 when there is no malfunction.   (b)Find the standard deviation of p .   (c)Compute an approximation for P≥p0.015 , which is the probability that the service technicians will be called even though the system is functioning properly. Round your answer to four decimal places.