Question

24

A smart phone manufacturer is interested in constructing a 95% confidence interval for the proportion of smart phones that break before the warranty expires. 85 of the 1622 randomly selected smart phones broke before the warranty expired. Round answers to 4 decimal places where possible.

a. With 95% confidence the proportion of all smart phones that break before the warranty expires is between and .

b. If many groups of 1622 randomly selected smart phones are selected, then a different confidence interval would be produced for each group. About percent of these confidence intervals will contain the true population proportion of all smart phones that break before the warranty expires and about percent will not contain the true population proportion.  

33

Using your favorite statistics software package, you generate a scatter plot with a regression equation and correlation coefficient. The regression equation is reported as

y=−14.35x+21.84

and the r=−0.11.

What percentage of the variation in y can be explained by the variation in the values of x?
r² = % (Report exact answer, and do not enter the % sign)

Answer 1

Question 24

a)

b)

If many groups of 1622 randomly selected smart phones are selected, then a different confidence interval would be produced for each group. About 95% percent of these confidence intervals will contain the true population proportion of all smart phones that break before the warranty expires and about 5% percent will not contain the true population proportion.

Dear student we can answer one question once post remaining separately