Answer:
At 0.10 significance level, there is significant evidence that the assembly time using the new method is faster
Step-by-step explanation:
Let mu be the true mean assembly time using the new method. Then hypotheses are:
mu = 42.3 min
mu < 42.3 min
Test statistic can be found using the equation:
t= where
- X is the sample mean assembly time (40.6 min)
- M is the mean assembly time using the present method (42.3)
- s is the sample standard deviation (2.7 min)
- N is the sample size (24)
Then t= ≈ −3,08
one tailed critical t-score of 0.10 significance level with 23 degrees of freedom is ≈ 1.319
Since −3,08<--1.319, we can reject the null hypothesis.
Thus, we can conclude that the assembly time using the new method is faster