Question

Using the information below, calculate a 95% T-confidence interval for the sample population. You have the mean, standard deviation and the sample size, all you have left to find is the T-critical value and you can calculate the interval.   PLEASE SHOW WORK

Once you calculate the confidence interval you will need to interpret your interval and explain what this means in words. Does your data follow a normal distribution?

Vehicle type/class	Year	Make	Model	Price
QUALITATIVE	QUANTITATIVE	QUALITATIVE	QUALITATIVE	QUANTITATIVE
Sedan	2019	A6	Audi	$64,236
Sedan	2019	Accord	Honda	$23,720
Sedan	2019	Altima	Nissan	$24,000
Sedan	2019	Corolla	Toyota	$18,700
Sedan	2019	LaCrosse	Buick	$29,570
Crossover	2019	CRV	Honda	$24,350
Crossover	2019	RAV4	Toyota	$25,650
SUV	2019	Navigator	Lincoln	$73,205
SUV	2019	Highlander	Toyota	$32,680
SUV	2019	Pilot	Honda	$31,450

Mean:	$34,756
Median:	$27,610
SD:	18487.275
Sample Size:	10

Answer 1

By 95% CI means- if we collect many random samples of same size & calculate CI for each of these sample, then in 95% of the cases population mean will lie within that that interval.

Below is the figure.

Above is the normality test done in minitab. Here we can see that p value is less than 0.05, thus we reject the null hypothesis (Data is normal - Null hypothesis & 0.05 is significance level).

Hence Data does not follow normal distribution.