Question

A truck driver wants to if there is a difference in salaries from dry van drivers to step deck drivers. He conducts a survey of 4 drive van drivers and finds that their average salary is $2032.50 every 2 weeks with a sample standard deviation of $39.48. He conducts the same survey on 3 step deck drivers and finds that their average salary is $2133.33 every 2 weeks with a sample standard deviation of $124.72. Using the critical values method at 99% confidence is there eitough evidence to support the claim that there is a difference if the average bi-weekly salaries. Use drive van drivers for mew 1.

Answer 1

has the symbol - then NOTE D If Ha the test would be left tailed 2) If He has the symbol > then the test would be right tailed. Type of statistic to be used; I since 1) n, =4<.30, =3 230 2) The standard deviations of two populations are not known We use 'ť statistic t = (x, 72) (4, -M2) S2 2 S U2 2 (2032.50–2133.33) -o [. We assume 139.99"7 12472 Ho is true and So M-M20 t=-1-35 3

: 't critical values: I corresponding to significance level (X). 100% -99% 1% = 0.01, degrees of free dom =n, the-2 = 4+3-2=5 and for two tailed test we get critical values 4.0322 NOTE: We can get these critical values by using either t critical value online calculator critical (or) t distributio Value table Conclusion: C.V=-4.0322 t=7.35 C.V=4.0322 Since 'ť statistic falls on the right side of critical value = -4.0322, we fail to reject Ho: M = 42 Hence there is ho sufficient evidence to conclude that there is a difference between bi weekly average salaries of van drivers and Deck drivers