In: Statistics and Probability
Coconut palm is a multiple use tree, and is consider as one of the ten most useful trees in the world. The heights of a sample of 15 full-grown coconut trees are given below in meters:
20.5, 30.1, 26.7, 22.7, 27.9, 30, 32.4, 20.7, 28.4, 25.9, 28.5, 23.8, 28, 29.4, 26.9
If the heights of all coconut trees are normally distributed, test that the mean height is greater than 25 meters.
1- What is the null hypothesis?
2- What is the alternative hypothesis?
3- What is the inference method?
4- What is the value of the test statistic?
5- What is the number of degrees of freedom of the test?
6- What is the p-value of the test?
7- What is your decision?
Question 7 options:
Reject the null hypothesis at level 0.05. |
|
Reject the alternative hypothesis at level 0.05. |
|
Fail to reject the null hypothesis at level 0.05. |
|
Reject the alternative hypothesis at level 0.05. |
Solution:
1) Null hypothesis is:- Ho: μ = 25
2) Alternative hypothesis is:- Ha: μ > 25
3) T-test for one sample mean (right tail)
4) Test statistic t= 1.987
5) degrees of freedom= n-1= 15-1= 14
6) p-value= 0.0334
7) Reject the null hypothesis at level 0.05
Calculations: