Question

CAN SOMEONE PLEASE HELP??????


Maintaining your balance may get harder as you grow older. A study was conducted to see how steady the elderly is on their feet. They had the subjects stand on a force platform and have them react to a noise. The force platform then measured how much they swayed forward and backward, and the data is in table #7.3.10 ("Maintaining balance while," 2013). Do the data show that the elderly sway more than the mean forward sway of younger people, which is 18.125 mm? Test at the 5% level.

Table #7.3.10: Forward/backward Sway (in mm) of Elderly Subjects

19

30

20

19

29

25

21

24

50

Answer 1

Answer:

Reject H0 and conclude that adults sway more than the mean forward sway for younger people.

Step-by-step explanation:

H0 : μ = 18.125

H0 : μ > 18.125

Sample data: 19 30 20 19 29 25 21 24 50

Sample size, n = 9

Sample mean, xbar = Σx / n = 237 / 9 = 26.333

Sample standard deviation, s = 9.772 (calculator)

The test statistic :

(xbar - μ) ÷ (s/√(n))

T = (26.333 - 18.125) ÷ (9.772/√(9))

T = 8.208 / 3.2573333

T = 2.519 = 2.520

Decison :

Reject H0 ; If Pvalue < α

The Pvalue :

Degree of freedom, df = n - 1 ; df = 9 - 1 = 8

Pvalue(2.520; 8) = 0.0179

Since 0.0179 < 0.05 ; WE reject H0 and conclude that adults sway more than the mean forward sway for younger people.