(a)
H0: Null Hypothesis: = 13.2
HA: Alternative Hypothesis: < 13.2
(b)
SE= s/
= 3.4/ = 0.4857
Test statistic is given by:
t = (11.9 - 13.2)/0.4857 = - 2.6765
(c)
= 0.01
ndf = n - 1 = 49 - 1 = 48
One Tail - Left Side Test
From Table, critical value of t = - 2.4066
Rejection Region:
Reject H0 if
t < - 2.4066
(d)
Since the calculated value of t = - 2.6765 is less than critical value of t = - 2.4066, the difference is significant. Reject null hypothesis.
Conclusion:
The data support the claim that mean number of days of skill training per year provided to employees by American businesses is less now.
(e)
t score = - 2.6765
ndf = 48
One Tail - Left Side Test
By Technology, P - Value = 0.0051
Since P - value= 0.0051 is less than = 0.01, the difference is significant. Reject null hypothesis.
Conclusion:
The data support the claim that mean number of days of skill training per year provided to employees by American businesses is less now.
32. Ten years ago the mean number of days of skill training per year provided to...
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