Question

The accompanying data represent the total travel tax​ (in dollars) for a​ 3-day business trip in 8 randomly selected cities. A normal probability plot suggests the data could come from a population that is normally distributed. A boxplot indicates there are no outliers. Complete parts​ (a) through​ (c) below. 67.88 78.86 69.13 83.59 79.73 86.64 101.37 99.93 LOADING... Click the icon to view the table of critical​ t-values. ​(a) Determine a point estimate for the population mean travel tax. A point estimate for the population mean travel tax is ​$ nothing. ​(Round to two decimal places as​ needed.) ​(b) Construct and interpret a 95​% confidence interval for the mean tax paid for a​ three-day business trip. Select the correct choice below and fill in the answer boxes to complete your choice. ​(Round to two decimal places as​ needed.) A. One can be nothing​% confident that the mean travel tax for all cities is between ​$ nothing and  ​$ nothing. B. One can be nothing​% confident that the all cities have a travel tax between ​$ nothing and ​$ nothing. C. There is a nothing​% probability that the mean travel tax for all cities is between ​$ nothing and ​$ nothing. D. The travel tax is between ​$ nothing and ​$ nothing for nothing​% of all cities. ​(c) What would you recommend to a researcher who wants to increase the precision of the​ interval, but does not have access to additional​ data? A. The researcher could decrease the level of confidence. B. The researcher could increase the level of confidence. C. The researcher could decrease the sample standard deviation. D. The researcher could increase the sample mean. Click to select your answer(s).

Answer 1

I will first calculate all the required measures needed to answer the questions and then answer the questions.

Mean and sample standard deviation calculation.

Confidence Interval calculation:

Answers)

A)Sample mean point Estimate:

Calculation shown above

B)95% Confidence Interval

(Calculated in the picture above and the sample standard deviation is calculated along with the mean.)
(72.982,93.8)

One can be nothing​ 95% confident that the mean travel tax for all cities is between ​$72.98 and $93.8

C) What would you recommend to a researcher who wants to increase the precision of the​ interval, but does not have access to additional​ data?

B. The researcher could increase the level of confidence. (95% to 96, 97 ,98 or 99 % confidence level)

C)