Homework Help

#1
Hello, I am struggling with this course. Can someone provide a step by step example of how to answer these questions?


In a survey of 703 randomly selected workers, 15.93% got their jobs through newspaper ads. Consider a hypothesis test that uses a 0.05 significance level to test the claim that less than 20% of workers get their jobs through newspaper ads.

What is the test statistic?

What is the critical value?

What is the P-value?

What is the conclusion?

Bases on the preceding results, can we conclude that 15.93% is significantly less than 20% for all such hypothesis tests?



Question #2

The Genetics and IVF Institute conducted a clinical trial of the YSORT method designed to increase the probability of conceiving a boy. 51 babies were born to parents using the YSORT method, and 39 of them were boys. Use the sample data with a 0.01 significance level to test the claim that with this method, the probability of a baby being a boy is greater than 0.5 Does the method appear to work?


Thanks for your help.
 
#3
John,

Thanks for the additional information, however, I am still unsure how this works. Please see my answer below for Question #2 and advise if I am on the right track.

Total = 51 babies
Boys = 39 out of 51
P=51/51+39=.5667

The probability of a baby being a boy is 56.67%.




Also, please provide guidance (step by step) in calculating the following:

Compare cardiac demands of snow shoveling to those of using an electric snow thrower.

Facts: Manual snow shoveling maximum heart rates: n=10, x=175, s=15
Electric snow thrower maximum heart rates: n=10, x=124, s=18.



Really appreciate the help.