Question

#2. Listed below are the amounts of net worth​ (in millions of​dollars) of the ten wealthiest celebrities in a country. Construct a 90​% confidence interval. What does the result tell us about the population of all​ celebrities? Do the data appear to be from a normally distributed population as​ required? 264 217 191 162 161 152 150 150 150 145 What is the confidence interval estimate of the population mean u ? ​

$------million<μ< $-------million (Round to one decimal place as​ needed.)

What does the result tell us about the population of all ​celebrities? Select the correct choice below​ and, if​ necessary, fill in the answer​box(es) to complete your choice. We are confident that 90​% of all celebrities have a net worth between $------million<μ< $-------million (Round to one decimal place as​ needed.)

We are 90​% confident that the interval from $------million<μ< $------- actually contains the true mean net worth of all celebrities. ​(Round to one decimal place as​needed.)

Because the ten wealthiest celebrities are not a representative​ sample, this​ doesn't provide any information about the population of all celebrities. Do the data appear to be from a normally distributed population as​ required?

A. ​Yes, but the points in the normal quantile plot do not lie reasonably close to a straight line or show a systematic pattern that is a straight line pattern.

B. ​Yes, because the pattern of the points in the normal quantile plot is reasonably close to a straight line.

C. ​No, because the points lie reasonably close to a straight​ line, but there is a systematic pattern that is not a straight line pattern.

D. ​No, but the points in the normal quantile plot lie reasonably close to a straight line and show some systematic pattern that is a straight line pattern.

#3. The pulse rates of 166 randomly selected adult males vary from a low of 35 bpm to a high of 107 bpm. Find the minimum sample size required to estimate the mean pulse rate of adult males. Assume that we want 98 % confidence that the sample mean is within 3 bpm of the population mean.

Find the sample size using the range rule of thumb to estimate q. N= ------ type whole number

B. assume that 10.7 bpm, based on values s= 10.7 bpm from the sample of 166 male pulse tares N= ------ type whole number

Compare the results from parts (a) and (b) which result is likely to be better?

The results from (a) is ----------- the results from part (b). The results from-------is likely to be better because ---------

#4. The Salaries of 45 college graduates who took a statistics course in college have a mean, x, of $ 64,900 . Assuming a standard deviation, q, of $19,881 , construct a 95 % confidence interval for estimating the population mean u. $ -----<μ< $------ round to nearest integer as needed

Answer 1

2)

sample std dev ,    s = √(Σ(X- x̅ )²/(n-1) ) =   38.8782
Sample Size ,   n =    10
Sample Mean,    x̅ = ΣX/n =    174.2000

Level of Significance ,    α =    0.1          
degree of freedom=   DF=n-1=   9          
't value='   tα/2=   1.833   [Excel formula =t.inv(α/2,df) ]      
                  
Standard Error , SE = s/√n =   38.8782   / √   10   =   12.2944
margin of error , E=t*SE =   1.8331   *   12.2944   =   22.5369
                  
confidence interval is                   
Interval Lower Limit = x̅ - E =    174.20   -   22.536937   =   151.6631
Interval Upper Limit = x̅ + E =    174.20   -   22.536937   =   196.7369
90%   confidence interval is (   151.7 < µ <   196.7 )

Because the ten wealthiest celebrities are not a representative​ sample, this​ doesn't provide any information about the population of all celebrities.

C. ​No, because the points lie reasonably close to a straight​line, but there is a systematic pattern that is not a straight line pattern.