Need help with Statistics. I will pay for the help if needed by assignment will be due soon. Is to much.

Question

In 1980 more than 35% of cars purchased had a manual transmission  (i.e. stick shift). By 2007 the proportion had decreased to 7.7% . A random sample of college students who owned cars revealed the following :Out of 127 cars, 27 had strick shift.  Estimate the proportion of college students who drives sticks  with 99% confidence.  Round to three decimal 

Answer 1

The formula for the confidence interval is  p±z∗square-root(p(1−p)/n)

 

P is the sample proportion which in this case is 27/127 = .2125984252

 

z is the confidence constant based on the normal curve which for 99% confidence level is 2.576

 

n = 127

 

The 99% confidence interval, courtesy of MS Excel is:

 

  (0.119075, 0.30612)

 

That is we are 99% that the REAL, Actual population

proportion lies inside this interval