SOLUTION: A field researcher is gathering data on the trunk diameters of mature pine and spruce trees in a certain area. The following are the results of his random sampling. Can he conclu

Question 1000225: A field researcher is gathering data on the trunk diameters of mature pine and spruce trees in a certain area. The following are the results of his random sampling. Can he conclude, at the 0.10 level of significance, that the average trunk diameter of a pine tree is greater than the average diameter of a spruce tree?

Pine trees
Spruce trees
Sample size
20
30
Mean trunk diameter (cm)
45
39
Sample variance
100
150

Answer by Boreal(15235) (Show Source): You can put this solution on YOUR website!
Ho same
Ha pine >spruce
alpha=0.10
one tailed 2-sample test
t with df=48
t=difference in means-0/sqrt (s1^2/n1)+(s2^2/n2))
on calculator get t=1.90, p-0.032
This is significantly different and reject Ho.
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