Question

Please help me with # 34

Thank you

Please show work with calculation

#34. (8pts) Suppose we randomly select five adults and they are given a Rubik's Cube to assemble it. Their length of time X (in minutes) required for each adult to assemble the cube was measured. They then consumed four straight shots of Vodka to raise their blood alcohol level. They assembled the cube again and the length of time was measured. Construct a 95% confidence interval for the unknown population mean difference in assembly times. Assume that the differences between the matched pairs come from a normally distributed population. You should show your work on computing the mean and standard deviation for the difference d ** X (Assembly time before alcohol consumption) Xz (Assembly time after alcohol consumption) d= X-X2(Difference in assembly times) 6 9 12 6 10 7

Answer 1

X1	X2	d
2	5	-3
3	7	-4
5	10	-5
6	12	-6
9	6	3
	Total	-15

Sample size = n = 5

Sample mean = $\bar{d}$ = - 3

Standard deviation = Sd = 3.5355

Level of confidence interval is

d-tc S/n< Pd < d+ tc * sa/Vn

Degrees of freedom = n - 1 = 5 - 1 = 4

tc = 2.776   ( Using t table)

$-3-2.776*3.5355/\sqrt{5}<\mu_{d}<-3-2.776*3.5355/\sqrt{5}$

$-3-4.3899<\mu_{d}<-3&plus;4.3899$

$-7.3899<\mu_{d}<1.3899$