!. According to a study on the effects of smoking by pregnant women on rates of asthma in their children, for expectant mothers who smoke 20 cigarettes per day, 22.7% of their children developed asthma by the age of two in the US. A biology professor at a university would like to test if the percentage is lower in another country. She randomly selects 344 women who only deliver one child and smoke 20 cigarettes per day during pregnancy in that country and finds that 67 of the children developed asthma by the age of two. In this hypothesis test,

the test statistic, z =

and the p-value =

(Round your answers to four decimal places.)

2.According to a Pew Research Center study, in May 2011, 31% of all American adults had a smart phone (one which the user can use to read email and surf the Internet). A communications professor at a university believes this percentage is higher among community college students. She selects 457 community college students at random and finds that 154 of them have a smart phone. Then in testing the hypotheses:

H0: p = 0.31 versus

Ha: p > 0.31,

what is the test statistic?

z = . (Please round your answer to two decimal places.)

3.A quality control engineer at a potato chip company tests the bag filling machine by weighing bags of potato chips. Not every bag contains exactly the same weight. But if more than 10% of bags are over-filled then they stop production to fix the machine. They define over-filled to be more than 1 ounce above the weight on the package.

The engineer weighs 149 bags and finds that 33 of them are over-filled. He plans to test the hypotheses H0: p = 0.1 versus Ha: p > 0.1. What is the test statistic?

z =

(Please round your answer to two decimal places if necessary.)