1.The quality-control manager at a light emitting diode (LED) factory needs to determine whether the mean life of a large shipment of LEDs is equal to 50,000 hours. The population standard deviation is 1,500 hours. A random sample of 64 LEDs indicates a sample mean life of 49,875 hours.

a. At the 0.05 level of significance, isthere evidence that the mean life is different from 50,000 hours?

Please use the Z or T approach.

2.A marketing researcher wants to estimate the mean amount spent per year ($) on Amazon.com by Amazon Prime member shoppers. Suppose a random sample of 100 Amazon Prime member shoppers who recently made a purchase on Amazon.com yielded a mean amount spent of $1,500 and a standard deviation of $200.

a. Is there evidence that the population mean amount spent per year on Amazon.com by Amazon Prime member shoppers is different from $1,475? (Use a 0.05 level of significance.)

3.According to a recent National Association of Colleges and Employers (NACE) report, 44% of college students who had unpaid internships received full-time job offers post-graduation compared to 72% of college students who had paid internships.

Source:Data extracted from "Here's Why You May Want to Rethink That Unpaid Internship," available at for.tn/29CAnU9.

A recent survey of 60 college unpaid interns at a local university found that 30 received full-time job offers post-graduation.

a. Use the six-stepp-value approach to hypothesis testing and a 0.05 level of significance to determine whether the proportion of college unpaid interns that received full-time job offers post-graduation is different from 0.44.

b. Assume that the study found that 35 of the 60 college unpaid interns had received full-time job offers post-graduation and repeat (a). Are the conclusions the same?

Use the Z or T approach FOR THESE Questions